.. | .. |
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2 | 2 | /* Copyright (c) 2018 Facebook */ |
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3 | 3 | |
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4 | 4 | #include <uapi/linux/btf.h> |
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| 5 | +#include <uapi/linux/bpf.h> |
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| 6 | +#include <uapi/linux/bpf_perf_event.h> |
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5 | 7 | #include <uapi/linux/types.h> |
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6 | 8 | #include <linux/seq_file.h> |
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7 | 9 | #include <linux/compiler.h> |
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.. | .. |
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16 | 18 | #include <linux/sort.h> |
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17 | 19 | #include <linux/bpf_verifier.h> |
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18 | 20 | #include <linux/btf.h> |
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| 21 | +#include <linux/btf_ids.h> |
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| 22 | +#include <linux/skmsg.h> |
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| 23 | +#include <linux/perf_event.h> |
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| 24 | +#include <linux/bsearch.h> |
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| 25 | +#include <linux/btf_ids.h> |
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| 26 | +#include <net/sock.h> |
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19 | 27 | |
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20 | 28 | /* BTF (BPF Type Format) is the meta data format which describes |
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21 | 29 | * the data types of BPF program/map. Hence, it basically focus |
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.. | .. |
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157 | 165 | * |
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158 | 166 | */ |
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159 | 167 | |
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160 | | -#define BITS_PER_U64 (sizeof(u64) * BITS_PER_BYTE) |
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| 168 | +#define BITS_PER_U128 (sizeof(u64) * BITS_PER_BYTE * 2) |
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161 | 169 | #define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1) |
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162 | 170 | #define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK) |
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163 | 171 | #define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3) |
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164 | 172 | #define BITS_ROUNDUP_BYTES(bits) \ |
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165 | 173 | (BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits)) |
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166 | 174 | |
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167 | | -#define BTF_INFO_MASK 0x0f00ffff |
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| 175 | +#define BTF_INFO_MASK 0x8f00ffff |
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168 | 176 | #define BTF_INT_MASK 0x0fffffff |
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169 | 177 | #define BTF_TYPE_ID_VALID(type_id) ((type_id) <= BTF_MAX_TYPE) |
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170 | 178 | #define BTF_STR_OFFSET_VALID(name_off) ((name_off) <= BTF_MAX_NAME_OFFSET) |
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.. | .. |
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175 | 183 | */ |
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176 | 184 | #define BTF_MAX_SIZE (16 * 1024 * 1024) |
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177 | 185 | |
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178 | | -#define for_each_member(i, struct_type, member) \ |
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179 | | - for (i = 0, member = btf_type_member(struct_type); \ |
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180 | | - i < btf_type_vlen(struct_type); \ |
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181 | | - i++, member++) |
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182 | | - |
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183 | 186 | #define for_each_member_from(i, from, struct_type, member) \ |
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184 | 187 | for (i = from, member = btf_type_member(struct_type) + from; \ |
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185 | 188 | i < btf_type_vlen(struct_type); \ |
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186 | 189 | i++, member++) |
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187 | 190 | |
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188 | | -static DEFINE_IDR(btf_idr); |
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189 | | -static DEFINE_SPINLOCK(btf_idr_lock); |
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| 191 | +#define for_each_vsi_from(i, from, struct_type, member) \ |
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| 192 | + for (i = from, member = btf_type_var_secinfo(struct_type) + from; \ |
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| 193 | + i < btf_type_vlen(struct_type); \ |
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| 194 | + i++, member++) |
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| 195 | + |
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| 196 | +DEFINE_IDR(btf_idr); |
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| 197 | +DEFINE_SPINLOCK(btf_idr_lock); |
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190 | 198 | |
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191 | 199 | struct btf { |
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192 | 200 | void *data; |
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.. | .. |
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260 | 268 | [BTF_KIND_VOLATILE] = "VOLATILE", |
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261 | 269 | [BTF_KIND_CONST] = "CONST", |
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262 | 270 | [BTF_KIND_RESTRICT] = "RESTRICT", |
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| 271 | + [BTF_KIND_FUNC] = "FUNC", |
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| 272 | + [BTF_KIND_FUNC_PROTO] = "FUNC_PROTO", |
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| 273 | + [BTF_KIND_VAR] = "VAR", |
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| 274 | + [BTF_KIND_DATASEC] = "DATASEC", |
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| 275 | +}; |
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| 276 | + |
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| 277 | +static const char *btf_type_str(const struct btf_type *t) |
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| 278 | +{ |
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| 279 | + return btf_kind_str[BTF_INFO_KIND(t->info)]; |
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| 280 | +} |
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| 281 | + |
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| 282 | +/* Chunk size we use in safe copy of data to be shown. */ |
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| 283 | +#define BTF_SHOW_OBJ_SAFE_SIZE 32 |
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| 284 | + |
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| 285 | +/* |
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| 286 | + * This is the maximum size of a base type value (equivalent to a |
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| 287 | + * 128-bit int); if we are at the end of our safe buffer and have |
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| 288 | + * less than 16 bytes space we can't be assured of being able |
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| 289 | + * to copy the next type safely, so in such cases we will initiate |
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| 290 | + * a new copy. |
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| 291 | + */ |
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| 292 | +#define BTF_SHOW_OBJ_BASE_TYPE_SIZE 16 |
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| 293 | + |
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| 294 | +/* Type name size */ |
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| 295 | +#define BTF_SHOW_NAME_SIZE 80 |
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| 296 | + |
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| 297 | +/* |
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| 298 | + * Common data to all BTF show operations. Private show functions can add |
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| 299 | + * their own data to a structure containing a struct btf_show and consult it |
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| 300 | + * in the show callback. See btf_type_show() below. |
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| 301 | + * |
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| 302 | + * One challenge with showing nested data is we want to skip 0-valued |
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| 303 | + * data, but in order to figure out whether a nested object is all zeros |
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| 304 | + * we need to walk through it. As a result, we need to make two passes |
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| 305 | + * when handling structs, unions and arrays; the first path simply looks |
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| 306 | + * for nonzero data, while the second actually does the display. The first |
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| 307 | + * pass is signalled by show->state.depth_check being set, and if we |
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| 308 | + * encounter a non-zero value we set show->state.depth_to_show to |
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| 309 | + * the depth at which we encountered it. When we have completed the |
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| 310 | + * first pass, we will know if anything needs to be displayed if |
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| 311 | + * depth_to_show > depth. See btf_[struct,array]_show() for the |
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| 312 | + * implementation of this. |
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| 313 | + * |
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| 314 | + * Another problem is we want to ensure the data for display is safe to |
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| 315 | + * access. To support this, the anonymous "struct {} obj" tracks the data |
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| 316 | + * object and our safe copy of it. We copy portions of the data needed |
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| 317 | + * to the object "copy" buffer, but because its size is limited to |
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| 318 | + * BTF_SHOW_OBJ_COPY_LEN bytes, multiple copies may be required as we |
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| 319 | + * traverse larger objects for display. |
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| 320 | + * |
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| 321 | + * The various data type show functions all start with a call to |
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| 322 | + * btf_show_start_type() which returns a pointer to the safe copy |
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| 323 | + * of the data needed (or if BTF_SHOW_UNSAFE is specified, to the |
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| 324 | + * raw data itself). btf_show_obj_safe() is responsible for |
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| 325 | + * using copy_from_kernel_nofault() to update the safe data if necessary |
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| 326 | + * as we traverse the object's data. skbuff-like semantics are |
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| 327 | + * used: |
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| 328 | + * |
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| 329 | + * - obj.head points to the start of the toplevel object for display |
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| 330 | + * - obj.size is the size of the toplevel object |
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| 331 | + * - obj.data points to the current point in the original data at |
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| 332 | + * which our safe data starts. obj.data will advance as we copy |
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| 333 | + * portions of the data. |
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| 334 | + * |
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| 335 | + * In most cases a single copy will suffice, but larger data structures |
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| 336 | + * such as "struct task_struct" will require many copies. The logic in |
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| 337 | + * btf_show_obj_safe() handles the logic that determines if a new |
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| 338 | + * copy_from_kernel_nofault() is needed. |
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| 339 | + */ |
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| 340 | +struct btf_show { |
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| 341 | + u64 flags; |
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| 342 | + void *target; /* target of show operation (seq file, buffer) */ |
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| 343 | + void (*showfn)(struct btf_show *show, const char *fmt, va_list args); |
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| 344 | + const struct btf *btf; |
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| 345 | + /* below are used during iteration */ |
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| 346 | + struct { |
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| 347 | + u8 depth; |
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| 348 | + u8 depth_to_show; |
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| 349 | + u8 depth_check; |
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| 350 | + u8 array_member:1, |
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| 351 | + array_terminated:1; |
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| 352 | + u16 array_encoding; |
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| 353 | + u32 type_id; |
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| 354 | + int status; /* non-zero for error */ |
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| 355 | + const struct btf_type *type; |
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| 356 | + const struct btf_member *member; |
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| 357 | + char name[BTF_SHOW_NAME_SIZE]; /* space for member name/type */ |
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| 358 | + } state; |
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| 359 | + struct { |
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| 360 | + u32 size; |
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| 361 | + void *head; |
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| 362 | + void *data; |
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| 363 | + u8 safe[BTF_SHOW_OBJ_SAFE_SIZE]; |
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| 364 | + } obj; |
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263 | 365 | }; |
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264 | 366 | |
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265 | 367 | struct btf_kind_operations { |
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.. | .. |
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272 | 374 | const struct btf_type *struct_type, |
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273 | 375 | const struct btf_member *member, |
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274 | 376 | const struct btf_type *member_type); |
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| 377 | + int (*check_kflag_member)(struct btf_verifier_env *env, |
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| 378 | + const struct btf_type *struct_type, |
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| 379 | + const struct btf_member *member, |
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| 380 | + const struct btf_type *member_type); |
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275 | 381 | void (*log_details)(struct btf_verifier_env *env, |
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276 | 382 | const struct btf_type *t); |
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277 | | - void (*seq_show)(const struct btf *btf, const struct btf_type *t, |
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| 383 | + void (*show)(const struct btf *btf, const struct btf_type *t, |
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278 | 384 | u32 type_id, void *data, u8 bits_offsets, |
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279 | | - struct seq_file *m); |
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| 385 | + struct btf_show *show); |
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280 | 386 | }; |
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281 | 387 | |
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282 | 388 | static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS]; |
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283 | 389 | static struct btf_type btf_void; |
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| 390 | + |
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| 391 | +static int btf_resolve(struct btf_verifier_env *env, |
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| 392 | + const struct btf_type *t, u32 type_id); |
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284 | 393 | |
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285 | 394 | static bool btf_type_is_modifier(const struct btf_type *t) |
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286 | 395 | { |
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.. | .. |
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305 | 414 | return false; |
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306 | 415 | } |
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307 | 416 | |
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308 | | -static bool btf_type_is_void(const struct btf_type *t) |
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| 417 | +bool btf_type_is_void(const struct btf_type *t) |
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309 | 418 | { |
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310 | | - /* void => no type and size info. |
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311 | | - * Hence, FWD is also treated as void. |
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312 | | - */ |
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313 | | - return t == &btf_void || BTF_INFO_KIND(t->info) == BTF_KIND_FWD; |
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| 419 | + return t == &btf_void; |
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314 | 420 | } |
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315 | 421 | |
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316 | | -static bool btf_type_is_void_or_null(const struct btf_type *t) |
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| 422 | +static bool btf_type_is_fwd(const struct btf_type *t) |
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317 | 423 | { |
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318 | | - return !t || btf_type_is_void(t); |
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| 424 | + return BTF_INFO_KIND(t->info) == BTF_KIND_FWD; |
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319 | 425 | } |
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320 | 426 | |
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321 | | -/* union is only a special case of struct: |
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322 | | - * all its offsetof(member) == 0 |
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323 | | - */ |
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324 | | -static bool btf_type_is_struct(const struct btf_type *t) |
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| 427 | +static bool btf_type_nosize(const struct btf_type *t) |
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325 | 428 | { |
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326 | | - u8 kind = BTF_INFO_KIND(t->info); |
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| 429 | + return btf_type_is_void(t) || btf_type_is_fwd(t) || |
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| 430 | + btf_type_is_func(t) || btf_type_is_func_proto(t); |
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| 431 | +} |
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327 | 432 | |
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328 | | - return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION; |
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| 433 | +static bool btf_type_nosize_or_null(const struct btf_type *t) |
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| 434 | +{ |
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| 435 | + return !t || btf_type_nosize(t); |
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| 436 | +} |
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| 437 | + |
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| 438 | +static bool __btf_type_is_struct(const struct btf_type *t) |
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| 439 | +{ |
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| 440 | + return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT; |
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329 | 441 | } |
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330 | 442 | |
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331 | 443 | static bool btf_type_is_array(const struct btf_type *t) |
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.. | .. |
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333 | 445 | return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY; |
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334 | 446 | } |
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335 | 447 | |
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336 | | -static bool btf_type_is_ptr(const struct btf_type *t) |
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| 448 | +static bool btf_type_is_datasec(const struct btf_type *t) |
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337 | 449 | { |
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338 | | - return BTF_INFO_KIND(t->info) == BTF_KIND_PTR; |
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| 450 | + return BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC; |
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339 | 451 | } |
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340 | 452 | |
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341 | | -static bool btf_type_is_int(const struct btf_type *t) |
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| 453 | +s32 btf_find_by_name_kind(const struct btf *btf, const char *name, u8 kind) |
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342 | 454 | { |
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343 | | - return BTF_INFO_KIND(t->info) == BTF_KIND_INT; |
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| 455 | + const struct btf_type *t; |
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| 456 | + const char *tname; |
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| 457 | + u32 i; |
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| 458 | + |
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| 459 | + for (i = 1; i <= btf->nr_types; i++) { |
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| 460 | + t = btf->types[i]; |
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| 461 | + if (BTF_INFO_KIND(t->info) != kind) |
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| 462 | + continue; |
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| 463 | + |
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| 464 | + tname = btf_name_by_offset(btf, t->name_off); |
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| 465 | + if (!strcmp(tname, name)) |
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| 466 | + return i; |
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| 467 | + } |
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| 468 | + |
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| 469 | + return -ENOENT; |
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| 470 | +} |
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| 471 | + |
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| 472 | +const struct btf_type *btf_type_skip_modifiers(const struct btf *btf, |
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| 473 | + u32 id, u32 *res_id) |
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| 474 | +{ |
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| 475 | + const struct btf_type *t = btf_type_by_id(btf, id); |
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| 476 | + |
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| 477 | + while (btf_type_is_modifier(t)) { |
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| 478 | + id = t->type; |
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| 479 | + t = btf_type_by_id(btf, t->type); |
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| 480 | + } |
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| 481 | + |
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| 482 | + if (res_id) |
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| 483 | + *res_id = id; |
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| 484 | + |
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| 485 | + return t; |
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| 486 | +} |
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| 487 | + |
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| 488 | +const struct btf_type *btf_type_resolve_ptr(const struct btf *btf, |
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| 489 | + u32 id, u32 *res_id) |
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| 490 | +{ |
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| 491 | + const struct btf_type *t; |
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| 492 | + |
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| 493 | + t = btf_type_skip_modifiers(btf, id, NULL); |
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| 494 | + if (!btf_type_is_ptr(t)) |
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| 495 | + return NULL; |
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| 496 | + |
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| 497 | + return btf_type_skip_modifiers(btf, t->type, res_id); |
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| 498 | +} |
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| 499 | + |
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| 500 | +const struct btf_type *btf_type_resolve_func_ptr(const struct btf *btf, |
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| 501 | + u32 id, u32 *res_id) |
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| 502 | +{ |
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| 503 | + const struct btf_type *ptype; |
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| 504 | + |
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| 505 | + ptype = btf_type_resolve_ptr(btf, id, res_id); |
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| 506 | + if (ptype && btf_type_is_func_proto(ptype)) |
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| 507 | + return ptype; |
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| 508 | + |
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| 509 | + return NULL; |
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| 510 | +} |
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| 511 | + |
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| 512 | +/* Types that act only as a source, not sink or intermediate |
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| 513 | + * type when resolving. |
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| 514 | + */ |
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| 515 | +static bool btf_type_is_resolve_source_only(const struct btf_type *t) |
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| 516 | +{ |
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| 517 | + return btf_type_is_var(t) || |
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| 518 | + btf_type_is_datasec(t); |
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344 | 519 | } |
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345 | 520 | |
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346 | 521 | /* What types need to be resolved? |
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.. | .. |
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349 | 524 | * |
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350 | 525 | * btf_type_is_struct() because its member refers to |
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351 | 526 | * another type (through member->type). |
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352 | | - |
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| 527 | + * |
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| 528 | + * btf_type_is_var() because the variable refers to |
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| 529 | + * another type. btf_type_is_datasec() holds multiple |
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| 530 | + * btf_type_is_var() types that need resolving. |
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| 531 | + * |
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353 | 532 | * btf_type_is_array() because its element (array->type) |
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354 | 533 | * refers to another type. Array can be thought of a |
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355 | 534 | * special case of struct while array just has the same |
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.. | .. |
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358 | 537 | static bool btf_type_needs_resolve(const struct btf_type *t) |
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359 | 538 | { |
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360 | 539 | return btf_type_is_modifier(t) || |
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361 | | - btf_type_is_ptr(t) || |
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362 | | - btf_type_is_struct(t) || |
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363 | | - btf_type_is_array(t); |
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| 540 | + btf_type_is_ptr(t) || |
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| 541 | + btf_type_is_struct(t) || |
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| 542 | + btf_type_is_array(t) || |
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| 543 | + btf_type_is_var(t) || |
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| 544 | + btf_type_is_datasec(t); |
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364 | 545 | } |
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365 | 546 | |
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366 | 547 | /* t->size can be used */ |
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.. | .. |
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371 | 552 | case BTF_KIND_STRUCT: |
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372 | 553 | case BTF_KIND_UNION: |
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373 | 554 | case BTF_KIND_ENUM: |
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| 555 | + case BTF_KIND_DATASEC: |
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374 | 556 | return true; |
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375 | 557 | } |
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376 | 558 | |
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.. | .. |
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391 | 573 | return "UNKN"; |
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392 | 574 | } |
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393 | 575 | |
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394 | | -static u16 btf_type_vlen(const struct btf_type *t) |
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395 | | -{ |
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396 | | - return BTF_INFO_VLEN(t->info); |
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397 | | -} |
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398 | | - |
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399 | 576 | static u32 btf_type_int(const struct btf_type *t) |
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400 | 577 | { |
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401 | 578 | return *(u32 *)(t + 1); |
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.. | .. |
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406 | 583 | return (const struct btf_array *)(t + 1); |
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407 | 584 | } |
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408 | 585 | |
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409 | | -static const struct btf_member *btf_type_member(const struct btf_type *t) |
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410 | | -{ |
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411 | | - return (const struct btf_member *)(t + 1); |
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412 | | -} |
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413 | | - |
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414 | 586 | static const struct btf_enum *btf_type_enum(const struct btf_type *t) |
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415 | 587 | { |
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416 | 588 | return (const struct btf_enum *)(t + 1); |
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| 589 | +} |
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| 590 | + |
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| 591 | +static const struct btf_var *btf_type_var(const struct btf_type *t) |
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| 592 | +{ |
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| 593 | + return (const struct btf_var *)(t + 1); |
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417 | 594 | } |
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418 | 595 | |
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419 | 596 | static const struct btf_kind_operations *btf_type_ops(const struct btf_type *t) |
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.. | .. |
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427 | 604 | offset < btf->hdr.str_len; |
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428 | 605 | } |
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429 | 606 | |
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430 | | -/* Only C-style identifier is permitted. This can be relaxed if |
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431 | | - * necessary. |
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432 | | - */ |
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433 | | -static bool btf_name_valid_identifier(const struct btf *btf, u32 offset) |
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| 607 | +static bool __btf_name_char_ok(char c, bool first, bool dot_ok) |
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| 608 | +{ |
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| 609 | + if ((first ? !isalpha(c) : |
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| 610 | + !isalnum(c)) && |
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| 611 | + c != '_' && |
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| 612 | + ((c == '.' && !dot_ok) || |
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| 613 | + c != '.')) |
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| 614 | + return false; |
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| 615 | + return true; |
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| 616 | +} |
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| 617 | + |
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| 618 | +static bool __btf_name_valid(const struct btf *btf, u32 offset, bool dot_ok) |
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434 | 619 | { |
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435 | 620 | /* offset must be valid */ |
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436 | 621 | const char *src = &btf->strings[offset]; |
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437 | 622 | const char *src_limit; |
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438 | 623 | |
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439 | | - if (!isalpha(*src) && *src != '_') |
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| 624 | + if (!__btf_name_char_ok(*src, true, dot_ok)) |
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440 | 625 | return false; |
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441 | 626 | |
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442 | 627 | /* set a limit on identifier length */ |
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443 | 628 | src_limit = src + KSYM_NAME_LEN; |
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444 | 629 | src++; |
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445 | 630 | while (*src && src < src_limit) { |
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446 | | - if (!isalnum(*src) && *src != '_') |
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| 631 | + if (!__btf_name_char_ok(*src, false, dot_ok)) |
---|
447 | 632 | return false; |
---|
448 | 633 | src++; |
---|
449 | 634 | } |
---|
.. | .. |
---|
451 | 636 | return !*src; |
---|
452 | 637 | } |
---|
453 | 638 | |
---|
454 | | -static const char *btf_name_by_offset(const struct btf *btf, u32 offset) |
---|
| 639 | +/* Only C-style identifier is permitted. This can be relaxed if |
---|
| 640 | + * necessary. |
---|
| 641 | + */ |
---|
| 642 | +static bool btf_name_valid_identifier(const struct btf *btf, u32 offset) |
---|
| 643 | +{ |
---|
| 644 | + return __btf_name_valid(btf, offset, false); |
---|
| 645 | +} |
---|
| 646 | + |
---|
| 647 | +static bool btf_name_valid_section(const struct btf *btf, u32 offset) |
---|
| 648 | +{ |
---|
| 649 | + return __btf_name_valid(btf, offset, true); |
---|
| 650 | +} |
---|
| 651 | + |
---|
| 652 | +static const char *__btf_name_by_offset(const struct btf *btf, u32 offset) |
---|
455 | 653 | { |
---|
456 | 654 | if (!offset) |
---|
457 | 655 | return "(anon)"; |
---|
.. | .. |
---|
461 | 659 | return "(invalid-name-offset)"; |
---|
462 | 660 | } |
---|
463 | 661 | |
---|
464 | | -static const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id) |
---|
| 662 | +const char *btf_name_by_offset(const struct btf *btf, u32 offset) |
---|
| 663 | +{ |
---|
| 664 | + if (offset < btf->hdr.str_len) |
---|
| 665 | + return &btf->strings[offset]; |
---|
| 666 | + |
---|
| 667 | + return NULL; |
---|
| 668 | +} |
---|
| 669 | + |
---|
| 670 | +const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id) |
---|
465 | 671 | { |
---|
466 | 672 | if (type_id > btf->nr_types) |
---|
467 | 673 | return NULL; |
---|
.. | .. |
---|
471 | 677 | |
---|
472 | 678 | /* |
---|
473 | 679 | * Regular int is not a bit field and it must be either |
---|
474 | | - * u8/u16/u32/u64. |
---|
| 680 | + * u8/u16/u32/u64 or __int128. |
---|
475 | 681 | */ |
---|
476 | 682 | static bool btf_type_int_is_regular(const struct btf_type *t) |
---|
477 | 683 | { |
---|
.. | .. |
---|
484 | 690 | if (BITS_PER_BYTE_MASKED(nr_bits) || |
---|
485 | 691 | BTF_INT_OFFSET(int_data) || |
---|
486 | 692 | (nr_bytes != sizeof(u8) && nr_bytes != sizeof(u16) && |
---|
487 | | - nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64))) { |
---|
| 693 | + nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64) && |
---|
| 694 | + nr_bytes != (2 * sizeof(u64)))) { |
---|
488 | 695 | return false; |
---|
489 | 696 | } |
---|
490 | 697 | |
---|
491 | 698 | return true; |
---|
| 699 | +} |
---|
| 700 | + |
---|
| 701 | +/* |
---|
| 702 | + * Check that given struct member is a regular int with expected |
---|
| 703 | + * offset and size. |
---|
| 704 | + */ |
---|
| 705 | +bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s, |
---|
| 706 | + const struct btf_member *m, |
---|
| 707 | + u32 expected_offset, u32 expected_size) |
---|
| 708 | +{ |
---|
| 709 | + const struct btf_type *t; |
---|
| 710 | + u32 id, int_data; |
---|
| 711 | + u8 nr_bits; |
---|
| 712 | + |
---|
| 713 | + id = m->type; |
---|
| 714 | + t = btf_type_id_size(btf, &id, NULL); |
---|
| 715 | + if (!t || !btf_type_is_int(t)) |
---|
| 716 | + return false; |
---|
| 717 | + |
---|
| 718 | + int_data = btf_type_int(t); |
---|
| 719 | + nr_bits = BTF_INT_BITS(int_data); |
---|
| 720 | + if (btf_type_kflag(s)) { |
---|
| 721 | + u32 bitfield_size = BTF_MEMBER_BITFIELD_SIZE(m->offset); |
---|
| 722 | + u32 bit_offset = BTF_MEMBER_BIT_OFFSET(m->offset); |
---|
| 723 | + |
---|
| 724 | + /* if kflag set, int should be a regular int and |
---|
| 725 | + * bit offset should be at byte boundary. |
---|
| 726 | + */ |
---|
| 727 | + return !bitfield_size && |
---|
| 728 | + BITS_ROUNDUP_BYTES(bit_offset) == expected_offset && |
---|
| 729 | + BITS_ROUNDUP_BYTES(nr_bits) == expected_size; |
---|
| 730 | + } |
---|
| 731 | + |
---|
| 732 | + if (BTF_INT_OFFSET(int_data) || |
---|
| 733 | + BITS_PER_BYTE_MASKED(m->offset) || |
---|
| 734 | + BITS_ROUNDUP_BYTES(m->offset) != expected_offset || |
---|
| 735 | + BITS_PER_BYTE_MASKED(nr_bits) || |
---|
| 736 | + BITS_ROUNDUP_BYTES(nr_bits) != expected_size) |
---|
| 737 | + return false; |
---|
| 738 | + |
---|
| 739 | + return true; |
---|
| 740 | +} |
---|
| 741 | + |
---|
| 742 | +/* Similar to btf_type_skip_modifiers() but does not skip typedefs. */ |
---|
| 743 | +static const struct btf_type *btf_type_skip_qualifiers(const struct btf *btf, |
---|
| 744 | + u32 id) |
---|
| 745 | +{ |
---|
| 746 | + const struct btf_type *t = btf_type_by_id(btf, id); |
---|
| 747 | + |
---|
| 748 | + while (btf_type_is_modifier(t) && |
---|
| 749 | + BTF_INFO_KIND(t->info) != BTF_KIND_TYPEDEF) { |
---|
| 750 | + id = t->type; |
---|
| 751 | + t = btf_type_by_id(btf, t->type); |
---|
| 752 | + } |
---|
| 753 | + |
---|
| 754 | + return t; |
---|
| 755 | +} |
---|
| 756 | + |
---|
| 757 | +#define BTF_SHOW_MAX_ITER 10 |
---|
| 758 | + |
---|
| 759 | +#define BTF_KIND_BIT(kind) (1ULL << kind) |
---|
| 760 | + |
---|
| 761 | +/* |
---|
| 762 | + * Populate show->state.name with type name information. |
---|
| 763 | + * Format of type name is |
---|
| 764 | + * |
---|
| 765 | + * [.member_name = ] (type_name) |
---|
| 766 | + */ |
---|
| 767 | +static const char *btf_show_name(struct btf_show *show) |
---|
| 768 | +{ |
---|
| 769 | + /* BTF_MAX_ITER array suffixes "[]" */ |
---|
| 770 | + const char *array_suffixes = "[][][][][][][][][][]"; |
---|
| 771 | + const char *array_suffix = &array_suffixes[strlen(array_suffixes)]; |
---|
| 772 | + /* BTF_MAX_ITER pointer suffixes "*" */ |
---|
| 773 | + const char *ptr_suffixes = "**********"; |
---|
| 774 | + const char *ptr_suffix = &ptr_suffixes[strlen(ptr_suffixes)]; |
---|
| 775 | + const char *name = NULL, *prefix = "", *parens = ""; |
---|
| 776 | + const struct btf_member *m = show->state.member; |
---|
| 777 | + const struct btf_type *t = show->state.type; |
---|
| 778 | + const struct btf_array *array; |
---|
| 779 | + u32 id = show->state.type_id; |
---|
| 780 | + const char *member = NULL; |
---|
| 781 | + bool show_member = false; |
---|
| 782 | + u64 kinds = 0; |
---|
| 783 | + int i; |
---|
| 784 | + |
---|
| 785 | + show->state.name[0] = '\0'; |
---|
| 786 | + |
---|
| 787 | + /* |
---|
| 788 | + * Don't show type name if we're showing an array member; |
---|
| 789 | + * in that case we show the array type so don't need to repeat |
---|
| 790 | + * ourselves for each member. |
---|
| 791 | + */ |
---|
| 792 | + if (show->state.array_member) |
---|
| 793 | + return ""; |
---|
| 794 | + |
---|
| 795 | + /* Retrieve member name, if any. */ |
---|
| 796 | + if (m) { |
---|
| 797 | + member = btf_name_by_offset(show->btf, m->name_off); |
---|
| 798 | + show_member = strlen(member) > 0; |
---|
| 799 | + id = m->type; |
---|
| 800 | + } |
---|
| 801 | + |
---|
| 802 | + /* |
---|
| 803 | + * Start with type_id, as we have resolved the struct btf_type * |
---|
| 804 | + * via btf_modifier_show() past the parent typedef to the child |
---|
| 805 | + * struct, int etc it is defined as. In such cases, the type_id |
---|
| 806 | + * still represents the starting type while the struct btf_type * |
---|
| 807 | + * in our show->state points at the resolved type of the typedef. |
---|
| 808 | + */ |
---|
| 809 | + t = btf_type_by_id(show->btf, id); |
---|
| 810 | + if (!t) |
---|
| 811 | + return ""; |
---|
| 812 | + |
---|
| 813 | + /* |
---|
| 814 | + * The goal here is to build up the right number of pointer and |
---|
| 815 | + * array suffixes while ensuring the type name for a typedef |
---|
| 816 | + * is represented. Along the way we accumulate a list of |
---|
| 817 | + * BTF kinds we have encountered, since these will inform later |
---|
| 818 | + * display; for example, pointer types will not require an |
---|
| 819 | + * opening "{" for struct, we will just display the pointer value. |
---|
| 820 | + * |
---|
| 821 | + * We also want to accumulate the right number of pointer or array |
---|
| 822 | + * indices in the format string while iterating until we get to |
---|
| 823 | + * the typedef/pointee/array member target type. |
---|
| 824 | + * |
---|
| 825 | + * We start by pointing at the end of pointer and array suffix |
---|
| 826 | + * strings; as we accumulate pointers and arrays we move the pointer |
---|
| 827 | + * or array string backwards so it will show the expected number of |
---|
| 828 | + * '*' or '[]' for the type. BTF_SHOW_MAX_ITER of nesting of pointers |
---|
| 829 | + * and/or arrays and typedefs are supported as a precaution. |
---|
| 830 | + * |
---|
| 831 | + * We also want to get typedef name while proceeding to resolve |
---|
| 832 | + * type it points to so that we can add parentheses if it is a |
---|
| 833 | + * "typedef struct" etc. |
---|
| 834 | + */ |
---|
| 835 | + for (i = 0; i < BTF_SHOW_MAX_ITER; i++) { |
---|
| 836 | + |
---|
| 837 | + switch (BTF_INFO_KIND(t->info)) { |
---|
| 838 | + case BTF_KIND_TYPEDEF: |
---|
| 839 | + if (!name) |
---|
| 840 | + name = btf_name_by_offset(show->btf, |
---|
| 841 | + t->name_off); |
---|
| 842 | + kinds |= BTF_KIND_BIT(BTF_KIND_TYPEDEF); |
---|
| 843 | + id = t->type; |
---|
| 844 | + break; |
---|
| 845 | + case BTF_KIND_ARRAY: |
---|
| 846 | + kinds |= BTF_KIND_BIT(BTF_KIND_ARRAY); |
---|
| 847 | + parens = "["; |
---|
| 848 | + if (!t) |
---|
| 849 | + return ""; |
---|
| 850 | + array = btf_type_array(t); |
---|
| 851 | + if (array_suffix > array_suffixes) |
---|
| 852 | + array_suffix -= 2; |
---|
| 853 | + id = array->type; |
---|
| 854 | + break; |
---|
| 855 | + case BTF_KIND_PTR: |
---|
| 856 | + kinds |= BTF_KIND_BIT(BTF_KIND_PTR); |
---|
| 857 | + if (ptr_suffix > ptr_suffixes) |
---|
| 858 | + ptr_suffix -= 1; |
---|
| 859 | + id = t->type; |
---|
| 860 | + break; |
---|
| 861 | + default: |
---|
| 862 | + id = 0; |
---|
| 863 | + break; |
---|
| 864 | + } |
---|
| 865 | + if (!id) |
---|
| 866 | + break; |
---|
| 867 | + t = btf_type_skip_qualifiers(show->btf, id); |
---|
| 868 | + } |
---|
| 869 | + /* We may not be able to represent this type; bail to be safe */ |
---|
| 870 | + if (i == BTF_SHOW_MAX_ITER) |
---|
| 871 | + return ""; |
---|
| 872 | + |
---|
| 873 | + if (!name) |
---|
| 874 | + name = btf_name_by_offset(show->btf, t->name_off); |
---|
| 875 | + |
---|
| 876 | + switch (BTF_INFO_KIND(t->info)) { |
---|
| 877 | + case BTF_KIND_STRUCT: |
---|
| 878 | + case BTF_KIND_UNION: |
---|
| 879 | + prefix = BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT ? |
---|
| 880 | + "struct" : "union"; |
---|
| 881 | + /* if it's an array of struct/union, parens is already set */ |
---|
| 882 | + if (!(kinds & (BTF_KIND_BIT(BTF_KIND_ARRAY)))) |
---|
| 883 | + parens = "{"; |
---|
| 884 | + break; |
---|
| 885 | + case BTF_KIND_ENUM: |
---|
| 886 | + prefix = "enum"; |
---|
| 887 | + break; |
---|
| 888 | + default: |
---|
| 889 | + break; |
---|
| 890 | + } |
---|
| 891 | + |
---|
| 892 | + /* pointer does not require parens */ |
---|
| 893 | + if (kinds & BTF_KIND_BIT(BTF_KIND_PTR)) |
---|
| 894 | + parens = ""; |
---|
| 895 | + /* typedef does not require struct/union/enum prefix */ |
---|
| 896 | + if (kinds & BTF_KIND_BIT(BTF_KIND_TYPEDEF)) |
---|
| 897 | + prefix = ""; |
---|
| 898 | + |
---|
| 899 | + if (!name) |
---|
| 900 | + name = ""; |
---|
| 901 | + |
---|
| 902 | + /* Even if we don't want type name info, we want parentheses etc */ |
---|
| 903 | + if (show->flags & BTF_SHOW_NONAME) |
---|
| 904 | + snprintf(show->state.name, sizeof(show->state.name), "%s", |
---|
| 905 | + parens); |
---|
| 906 | + else |
---|
| 907 | + snprintf(show->state.name, sizeof(show->state.name), |
---|
| 908 | + "%s%s%s(%s%s%s%s%s%s)%s", |
---|
| 909 | + /* first 3 strings comprise ".member = " */ |
---|
| 910 | + show_member ? "." : "", |
---|
| 911 | + show_member ? member : "", |
---|
| 912 | + show_member ? " = " : "", |
---|
| 913 | + /* ...next is our prefix (struct, enum, etc) */ |
---|
| 914 | + prefix, |
---|
| 915 | + strlen(prefix) > 0 && strlen(name) > 0 ? " " : "", |
---|
| 916 | + /* ...this is the type name itself */ |
---|
| 917 | + name, |
---|
| 918 | + /* ...suffixed by the appropriate '*', '[]' suffixes */ |
---|
| 919 | + strlen(ptr_suffix) > 0 ? " " : "", ptr_suffix, |
---|
| 920 | + array_suffix, parens); |
---|
| 921 | + |
---|
| 922 | + return show->state.name; |
---|
| 923 | +} |
---|
| 924 | + |
---|
| 925 | +static const char *__btf_show_indent(struct btf_show *show) |
---|
| 926 | +{ |
---|
| 927 | + const char *indents = " "; |
---|
| 928 | + const char *indent = &indents[strlen(indents)]; |
---|
| 929 | + |
---|
| 930 | + if ((indent - show->state.depth) >= indents) |
---|
| 931 | + return indent - show->state.depth; |
---|
| 932 | + return indents; |
---|
| 933 | +} |
---|
| 934 | + |
---|
| 935 | +static const char *btf_show_indent(struct btf_show *show) |
---|
| 936 | +{ |
---|
| 937 | + return show->flags & BTF_SHOW_COMPACT ? "" : __btf_show_indent(show); |
---|
| 938 | +} |
---|
| 939 | + |
---|
| 940 | +static const char *btf_show_newline(struct btf_show *show) |
---|
| 941 | +{ |
---|
| 942 | + return show->flags & BTF_SHOW_COMPACT ? "" : "\n"; |
---|
| 943 | +} |
---|
| 944 | + |
---|
| 945 | +static const char *btf_show_delim(struct btf_show *show) |
---|
| 946 | +{ |
---|
| 947 | + if (show->state.depth == 0) |
---|
| 948 | + return ""; |
---|
| 949 | + |
---|
| 950 | + if ((show->flags & BTF_SHOW_COMPACT) && show->state.type && |
---|
| 951 | + BTF_INFO_KIND(show->state.type->info) == BTF_KIND_UNION) |
---|
| 952 | + return "|"; |
---|
| 953 | + |
---|
| 954 | + return ","; |
---|
| 955 | +} |
---|
| 956 | + |
---|
| 957 | +__printf(2, 3) static void btf_show(struct btf_show *show, const char *fmt, ...) |
---|
| 958 | +{ |
---|
| 959 | + va_list args; |
---|
| 960 | + |
---|
| 961 | + if (!show->state.depth_check) { |
---|
| 962 | + va_start(args, fmt); |
---|
| 963 | + show->showfn(show, fmt, args); |
---|
| 964 | + va_end(args); |
---|
| 965 | + } |
---|
| 966 | +} |
---|
| 967 | + |
---|
| 968 | +/* Macros are used here as btf_show_type_value[s]() prepends and appends |
---|
| 969 | + * format specifiers to the format specifier passed in; these do the work of |
---|
| 970 | + * adding indentation, delimiters etc while the caller simply has to specify |
---|
| 971 | + * the type value(s) in the format specifier + value(s). |
---|
| 972 | + */ |
---|
| 973 | +#define btf_show_type_value(show, fmt, value) \ |
---|
| 974 | + do { \ |
---|
| 975 | + if ((value) != 0 || (show->flags & BTF_SHOW_ZERO) || \ |
---|
| 976 | + show->state.depth == 0) { \ |
---|
| 977 | + btf_show(show, "%s%s" fmt "%s%s", \ |
---|
| 978 | + btf_show_indent(show), \ |
---|
| 979 | + btf_show_name(show), \ |
---|
| 980 | + value, btf_show_delim(show), \ |
---|
| 981 | + btf_show_newline(show)); \ |
---|
| 982 | + if (show->state.depth > show->state.depth_to_show) \ |
---|
| 983 | + show->state.depth_to_show = show->state.depth; \ |
---|
| 984 | + } \ |
---|
| 985 | + } while (0) |
---|
| 986 | + |
---|
| 987 | +#define btf_show_type_values(show, fmt, ...) \ |
---|
| 988 | + do { \ |
---|
| 989 | + btf_show(show, "%s%s" fmt "%s%s", btf_show_indent(show), \ |
---|
| 990 | + btf_show_name(show), \ |
---|
| 991 | + __VA_ARGS__, btf_show_delim(show), \ |
---|
| 992 | + btf_show_newline(show)); \ |
---|
| 993 | + if (show->state.depth > show->state.depth_to_show) \ |
---|
| 994 | + show->state.depth_to_show = show->state.depth; \ |
---|
| 995 | + } while (0) |
---|
| 996 | + |
---|
| 997 | +/* How much is left to copy to safe buffer after @data? */ |
---|
| 998 | +static int btf_show_obj_size_left(struct btf_show *show, void *data) |
---|
| 999 | +{ |
---|
| 1000 | + return show->obj.head + show->obj.size - data; |
---|
| 1001 | +} |
---|
| 1002 | + |
---|
| 1003 | +/* Is object pointed to by @data of @size already copied to our safe buffer? */ |
---|
| 1004 | +static bool btf_show_obj_is_safe(struct btf_show *show, void *data, int size) |
---|
| 1005 | +{ |
---|
| 1006 | + return data >= show->obj.data && |
---|
| 1007 | + (data + size) < (show->obj.data + BTF_SHOW_OBJ_SAFE_SIZE); |
---|
| 1008 | +} |
---|
| 1009 | + |
---|
| 1010 | +/* |
---|
| 1011 | + * If object pointed to by @data of @size falls within our safe buffer, return |
---|
| 1012 | + * the equivalent pointer to the same safe data. Assumes |
---|
| 1013 | + * copy_from_kernel_nofault() has already happened and our safe buffer is |
---|
| 1014 | + * populated. |
---|
| 1015 | + */ |
---|
| 1016 | +static void *__btf_show_obj_safe(struct btf_show *show, void *data, int size) |
---|
| 1017 | +{ |
---|
| 1018 | + if (btf_show_obj_is_safe(show, data, size)) |
---|
| 1019 | + return show->obj.safe + (data - show->obj.data); |
---|
| 1020 | + return NULL; |
---|
| 1021 | +} |
---|
| 1022 | + |
---|
| 1023 | +/* |
---|
| 1024 | + * Return a safe-to-access version of data pointed to by @data. |
---|
| 1025 | + * We do this by copying the relevant amount of information |
---|
| 1026 | + * to the struct btf_show obj.safe buffer using copy_from_kernel_nofault(). |
---|
| 1027 | + * |
---|
| 1028 | + * If BTF_SHOW_UNSAFE is specified, just return data as-is; no |
---|
| 1029 | + * safe copy is needed. |
---|
| 1030 | + * |
---|
| 1031 | + * Otherwise we need to determine if we have the required amount |
---|
| 1032 | + * of data (determined by the @data pointer and the size of the |
---|
| 1033 | + * largest base type we can encounter (represented by |
---|
| 1034 | + * BTF_SHOW_OBJ_BASE_TYPE_SIZE). Having that much data ensures |
---|
| 1035 | + * that we will be able to print some of the current object, |
---|
| 1036 | + * and if more is needed a copy will be triggered. |
---|
| 1037 | + * Some objects such as structs will not fit into the buffer; |
---|
| 1038 | + * in such cases additional copies when we iterate over their |
---|
| 1039 | + * members may be needed. |
---|
| 1040 | + * |
---|
| 1041 | + * btf_show_obj_safe() is used to return a safe buffer for |
---|
| 1042 | + * btf_show_start_type(); this ensures that as we recurse into |
---|
| 1043 | + * nested types we always have safe data for the given type. |
---|
| 1044 | + * This approach is somewhat wasteful; it's possible for example |
---|
| 1045 | + * that when iterating over a large union we'll end up copying the |
---|
| 1046 | + * same data repeatedly, but the goal is safety not performance. |
---|
| 1047 | + * We use stack data as opposed to per-CPU buffers because the |
---|
| 1048 | + * iteration over a type can take some time, and preemption handling |
---|
| 1049 | + * would greatly complicate use of the safe buffer. |
---|
| 1050 | + */ |
---|
| 1051 | +static void *btf_show_obj_safe(struct btf_show *show, |
---|
| 1052 | + const struct btf_type *t, |
---|
| 1053 | + void *data) |
---|
| 1054 | +{ |
---|
| 1055 | + const struct btf_type *rt; |
---|
| 1056 | + int size_left, size; |
---|
| 1057 | + void *safe = NULL; |
---|
| 1058 | + |
---|
| 1059 | + if (show->flags & BTF_SHOW_UNSAFE) |
---|
| 1060 | + return data; |
---|
| 1061 | + |
---|
| 1062 | + rt = btf_resolve_size(show->btf, t, &size); |
---|
| 1063 | + if (IS_ERR(rt)) { |
---|
| 1064 | + show->state.status = PTR_ERR(rt); |
---|
| 1065 | + return NULL; |
---|
| 1066 | + } |
---|
| 1067 | + |
---|
| 1068 | + /* |
---|
| 1069 | + * Is this toplevel object? If so, set total object size and |
---|
| 1070 | + * initialize pointers. Otherwise check if we still fall within |
---|
| 1071 | + * our safe object data. |
---|
| 1072 | + */ |
---|
| 1073 | + if (show->state.depth == 0) { |
---|
| 1074 | + show->obj.size = size; |
---|
| 1075 | + show->obj.head = data; |
---|
| 1076 | + } else { |
---|
| 1077 | + /* |
---|
| 1078 | + * If the size of the current object is > our remaining |
---|
| 1079 | + * safe buffer we _may_ need to do a new copy. However |
---|
| 1080 | + * consider the case of a nested struct; it's size pushes |
---|
| 1081 | + * us over the safe buffer limit, but showing any individual |
---|
| 1082 | + * struct members does not. In such cases, we don't need |
---|
| 1083 | + * to initiate a fresh copy yet; however we definitely need |
---|
| 1084 | + * at least BTF_SHOW_OBJ_BASE_TYPE_SIZE bytes left |
---|
| 1085 | + * in our buffer, regardless of the current object size. |
---|
| 1086 | + * The logic here is that as we resolve types we will |
---|
| 1087 | + * hit a base type at some point, and we need to be sure |
---|
| 1088 | + * the next chunk of data is safely available to display |
---|
| 1089 | + * that type info safely. We cannot rely on the size of |
---|
| 1090 | + * the current object here because it may be much larger |
---|
| 1091 | + * than our current buffer (e.g. task_struct is 8k). |
---|
| 1092 | + * All we want to do here is ensure that we can print the |
---|
| 1093 | + * next basic type, which we can if either |
---|
| 1094 | + * - the current type size is within the safe buffer; or |
---|
| 1095 | + * - at least BTF_SHOW_OBJ_BASE_TYPE_SIZE bytes are left in |
---|
| 1096 | + * the safe buffer. |
---|
| 1097 | + */ |
---|
| 1098 | + safe = __btf_show_obj_safe(show, data, |
---|
| 1099 | + min(size, |
---|
| 1100 | + BTF_SHOW_OBJ_BASE_TYPE_SIZE)); |
---|
| 1101 | + } |
---|
| 1102 | + |
---|
| 1103 | + /* |
---|
| 1104 | + * We need a new copy to our safe object, either because we haven't |
---|
| 1105 | + * yet copied and are intializing safe data, or because the data |
---|
| 1106 | + * we want falls outside the boundaries of the safe object. |
---|
| 1107 | + */ |
---|
| 1108 | + if (!safe) { |
---|
| 1109 | + size_left = btf_show_obj_size_left(show, data); |
---|
| 1110 | + if (size_left > BTF_SHOW_OBJ_SAFE_SIZE) |
---|
| 1111 | + size_left = BTF_SHOW_OBJ_SAFE_SIZE; |
---|
| 1112 | + show->state.status = copy_from_kernel_nofault(show->obj.safe, |
---|
| 1113 | + data, size_left); |
---|
| 1114 | + if (!show->state.status) { |
---|
| 1115 | + show->obj.data = data; |
---|
| 1116 | + safe = show->obj.safe; |
---|
| 1117 | + } |
---|
| 1118 | + } |
---|
| 1119 | + |
---|
| 1120 | + return safe; |
---|
| 1121 | +} |
---|
| 1122 | + |
---|
| 1123 | +/* |
---|
| 1124 | + * Set the type we are starting to show and return a safe data pointer |
---|
| 1125 | + * to be used for showing the associated data. |
---|
| 1126 | + */ |
---|
| 1127 | +static void *btf_show_start_type(struct btf_show *show, |
---|
| 1128 | + const struct btf_type *t, |
---|
| 1129 | + u32 type_id, void *data) |
---|
| 1130 | +{ |
---|
| 1131 | + show->state.type = t; |
---|
| 1132 | + show->state.type_id = type_id; |
---|
| 1133 | + show->state.name[0] = '\0'; |
---|
| 1134 | + |
---|
| 1135 | + return btf_show_obj_safe(show, t, data); |
---|
| 1136 | +} |
---|
| 1137 | + |
---|
| 1138 | +static void btf_show_end_type(struct btf_show *show) |
---|
| 1139 | +{ |
---|
| 1140 | + show->state.type = NULL; |
---|
| 1141 | + show->state.type_id = 0; |
---|
| 1142 | + show->state.name[0] = '\0'; |
---|
| 1143 | +} |
---|
| 1144 | + |
---|
| 1145 | +static void *btf_show_start_aggr_type(struct btf_show *show, |
---|
| 1146 | + const struct btf_type *t, |
---|
| 1147 | + u32 type_id, void *data) |
---|
| 1148 | +{ |
---|
| 1149 | + void *safe_data = btf_show_start_type(show, t, type_id, data); |
---|
| 1150 | + |
---|
| 1151 | + if (!safe_data) |
---|
| 1152 | + return safe_data; |
---|
| 1153 | + |
---|
| 1154 | + btf_show(show, "%s%s%s", btf_show_indent(show), |
---|
| 1155 | + btf_show_name(show), |
---|
| 1156 | + btf_show_newline(show)); |
---|
| 1157 | + show->state.depth++; |
---|
| 1158 | + return safe_data; |
---|
| 1159 | +} |
---|
| 1160 | + |
---|
| 1161 | +static void btf_show_end_aggr_type(struct btf_show *show, |
---|
| 1162 | + const char *suffix) |
---|
| 1163 | +{ |
---|
| 1164 | + show->state.depth--; |
---|
| 1165 | + btf_show(show, "%s%s%s%s", btf_show_indent(show), suffix, |
---|
| 1166 | + btf_show_delim(show), btf_show_newline(show)); |
---|
| 1167 | + btf_show_end_type(show); |
---|
| 1168 | +} |
---|
| 1169 | + |
---|
| 1170 | +static void btf_show_start_member(struct btf_show *show, |
---|
| 1171 | + const struct btf_member *m) |
---|
| 1172 | +{ |
---|
| 1173 | + show->state.member = m; |
---|
| 1174 | +} |
---|
| 1175 | + |
---|
| 1176 | +static void btf_show_start_array_member(struct btf_show *show) |
---|
| 1177 | +{ |
---|
| 1178 | + show->state.array_member = 1; |
---|
| 1179 | + btf_show_start_member(show, NULL); |
---|
| 1180 | +} |
---|
| 1181 | + |
---|
| 1182 | +static void btf_show_end_member(struct btf_show *show) |
---|
| 1183 | +{ |
---|
| 1184 | + show->state.member = NULL; |
---|
| 1185 | +} |
---|
| 1186 | + |
---|
| 1187 | +static void btf_show_end_array_member(struct btf_show *show) |
---|
| 1188 | +{ |
---|
| 1189 | + show->state.array_member = 0; |
---|
| 1190 | + btf_show_end_member(show); |
---|
| 1191 | +} |
---|
| 1192 | + |
---|
| 1193 | +static void *btf_show_start_array_type(struct btf_show *show, |
---|
| 1194 | + const struct btf_type *t, |
---|
| 1195 | + u32 type_id, |
---|
| 1196 | + u16 array_encoding, |
---|
| 1197 | + void *data) |
---|
| 1198 | +{ |
---|
| 1199 | + show->state.array_encoding = array_encoding; |
---|
| 1200 | + show->state.array_terminated = 0; |
---|
| 1201 | + return btf_show_start_aggr_type(show, t, type_id, data); |
---|
| 1202 | +} |
---|
| 1203 | + |
---|
| 1204 | +static void btf_show_end_array_type(struct btf_show *show) |
---|
| 1205 | +{ |
---|
| 1206 | + show->state.array_encoding = 0; |
---|
| 1207 | + show->state.array_terminated = 0; |
---|
| 1208 | + btf_show_end_aggr_type(show, "]"); |
---|
| 1209 | +} |
---|
| 1210 | + |
---|
| 1211 | +static void *btf_show_start_struct_type(struct btf_show *show, |
---|
| 1212 | + const struct btf_type *t, |
---|
| 1213 | + u32 type_id, |
---|
| 1214 | + void *data) |
---|
| 1215 | +{ |
---|
| 1216 | + return btf_show_start_aggr_type(show, t, type_id, data); |
---|
| 1217 | +} |
---|
| 1218 | + |
---|
| 1219 | +static void btf_show_end_struct_type(struct btf_show *show) |
---|
| 1220 | +{ |
---|
| 1221 | + btf_show_end_aggr_type(show, "}"); |
---|
492 | 1222 | } |
---|
493 | 1223 | |
---|
494 | 1224 | __printf(2, 3) static void __btf_verifier_log(struct bpf_verifier_log *log, |
---|
.. | .. |
---|
528 | 1258 | if (!bpf_verifier_log_needed(log)) |
---|
529 | 1259 | return; |
---|
530 | 1260 | |
---|
| 1261 | + /* btf verifier prints all types it is processing via |
---|
| 1262 | + * btf_verifier_log_type(..., fmt = NULL). |
---|
| 1263 | + * Skip those prints for in-kernel BTF verification. |
---|
| 1264 | + */ |
---|
| 1265 | + if (log->level == BPF_LOG_KERNEL && !fmt) |
---|
| 1266 | + return; |
---|
| 1267 | + |
---|
531 | 1268 | __btf_verifier_log(log, "[%u] %s %s%s", |
---|
532 | 1269 | env->log_type_id, |
---|
533 | 1270 | btf_kind_str[kind], |
---|
534 | | - btf_name_by_offset(btf, t->name_off), |
---|
| 1271 | + __btf_name_by_offset(btf, t->name_off), |
---|
535 | 1272 | log_details ? " " : ""); |
---|
536 | 1273 | |
---|
537 | 1274 | if (log_details) |
---|
.. | .. |
---|
565 | 1302 | if (!bpf_verifier_log_needed(log)) |
---|
566 | 1303 | return; |
---|
567 | 1304 | |
---|
| 1305 | + if (log->level == BPF_LOG_KERNEL && !fmt) |
---|
| 1306 | + return; |
---|
568 | 1307 | /* The CHECK_META phase already did a btf dump. |
---|
569 | 1308 | * |
---|
570 | 1309 | * If member is logged again, it must hit an error in |
---|
.. | .. |
---|
574 | 1313 | if (env->phase != CHECK_META) |
---|
575 | 1314 | btf_verifier_log_type(env, struct_type, NULL); |
---|
576 | 1315 | |
---|
577 | | - __btf_verifier_log(log, "\t%s type_id=%u bits_offset=%u", |
---|
578 | | - btf_name_by_offset(btf, member->name_off), |
---|
579 | | - member->type, member->offset); |
---|
| 1316 | + if (btf_type_kflag(struct_type)) |
---|
| 1317 | + __btf_verifier_log(log, |
---|
| 1318 | + "\t%s type_id=%u bitfield_size=%u bits_offset=%u", |
---|
| 1319 | + __btf_name_by_offset(btf, member->name_off), |
---|
| 1320 | + member->type, |
---|
| 1321 | + BTF_MEMBER_BITFIELD_SIZE(member->offset), |
---|
| 1322 | + BTF_MEMBER_BIT_OFFSET(member->offset)); |
---|
| 1323 | + else |
---|
| 1324 | + __btf_verifier_log(log, "\t%s type_id=%u bits_offset=%u", |
---|
| 1325 | + __btf_name_by_offset(btf, member->name_off), |
---|
| 1326 | + member->type, member->offset); |
---|
580 | 1327 | |
---|
| 1328 | + if (fmt && *fmt) { |
---|
| 1329 | + __btf_verifier_log(log, " "); |
---|
| 1330 | + va_start(args, fmt); |
---|
| 1331 | + bpf_verifier_vlog(log, fmt, args); |
---|
| 1332 | + va_end(args); |
---|
| 1333 | + } |
---|
| 1334 | + |
---|
| 1335 | + __btf_verifier_log(log, "\n"); |
---|
| 1336 | +} |
---|
| 1337 | + |
---|
| 1338 | +__printf(4, 5) |
---|
| 1339 | +static void btf_verifier_log_vsi(struct btf_verifier_env *env, |
---|
| 1340 | + const struct btf_type *datasec_type, |
---|
| 1341 | + const struct btf_var_secinfo *vsi, |
---|
| 1342 | + const char *fmt, ...) |
---|
| 1343 | +{ |
---|
| 1344 | + struct bpf_verifier_log *log = &env->log; |
---|
| 1345 | + va_list args; |
---|
| 1346 | + |
---|
| 1347 | + if (!bpf_verifier_log_needed(log)) |
---|
| 1348 | + return; |
---|
| 1349 | + if (log->level == BPF_LOG_KERNEL && !fmt) |
---|
| 1350 | + return; |
---|
| 1351 | + if (env->phase != CHECK_META) |
---|
| 1352 | + btf_verifier_log_type(env, datasec_type, NULL); |
---|
| 1353 | + |
---|
| 1354 | + __btf_verifier_log(log, "\t type_id=%u offset=%u size=%u", |
---|
| 1355 | + vsi->type, vsi->offset, vsi->size); |
---|
581 | 1356 | if (fmt && *fmt) { |
---|
582 | 1357 | __btf_verifier_log(log, " "); |
---|
583 | 1358 | va_start(args, fmt); |
---|
.. | .. |
---|
598 | 1373 | if (!bpf_verifier_log_needed(log)) |
---|
599 | 1374 | return; |
---|
600 | 1375 | |
---|
| 1376 | + if (log->level == BPF_LOG_KERNEL) |
---|
| 1377 | + return; |
---|
601 | 1378 | hdr = &btf->hdr; |
---|
602 | 1379 | __btf_verifier_log(log, "magic: 0x%x\n", hdr->magic); |
---|
603 | 1380 | __btf_verifier_log(log, "version: %u\n", hdr->version); |
---|
.. | .. |
---|
765 | 1542 | /* int, enum or void is a sink */ |
---|
766 | 1543 | return !btf_type_needs_resolve(next_type); |
---|
767 | 1544 | case RESOLVE_PTR: |
---|
768 | | - /* int, enum, void, struct or array is a sink for ptr */ |
---|
| 1545 | + /* int, enum, void, struct, array, func or func_proto is a sink |
---|
| 1546 | + * for ptr |
---|
| 1547 | + */ |
---|
769 | 1548 | return !btf_type_is_modifier(next_type) && |
---|
770 | 1549 | !btf_type_is_ptr(next_type); |
---|
771 | 1550 | case RESOLVE_STRUCT_OR_ARRAY: |
---|
772 | | - /* int, enum, void or ptr is a sink for struct and array */ |
---|
| 1551 | + /* int, enum, void, ptr, func or func_proto is a sink |
---|
| 1552 | + * for struct and array |
---|
| 1553 | + */ |
---|
773 | 1554 | return !btf_type_is_modifier(next_type) && |
---|
774 | 1555 | !btf_type_is_array(next_type) && |
---|
775 | 1556 | !btf_type_is_struct(next_type); |
---|
.. | .. |
---|
835 | 1616 | return env->top_stack ? &env->stack[env->top_stack - 1] : NULL; |
---|
836 | 1617 | } |
---|
837 | 1618 | |
---|
| 1619 | +/* Resolve the size of a passed-in "type" |
---|
| 1620 | + * |
---|
| 1621 | + * type: is an array (e.g. u32 array[x][y]) |
---|
| 1622 | + * return type: type "u32[x][y]", i.e. BTF_KIND_ARRAY, |
---|
| 1623 | + * *type_size: (x * y * sizeof(u32)). Hence, *type_size always |
---|
| 1624 | + * corresponds to the return type. |
---|
| 1625 | + * *elem_type: u32 |
---|
| 1626 | + * *elem_id: id of u32 |
---|
| 1627 | + * *total_nelems: (x * y). Hence, individual elem size is |
---|
| 1628 | + * (*type_size / *total_nelems) |
---|
| 1629 | + * *type_id: id of type if it's changed within the function, 0 if not |
---|
| 1630 | + * |
---|
| 1631 | + * type: is not an array (e.g. const struct X) |
---|
| 1632 | + * return type: type "struct X" |
---|
| 1633 | + * *type_size: sizeof(struct X) |
---|
| 1634 | + * *elem_type: same as return type ("struct X") |
---|
| 1635 | + * *elem_id: 0 |
---|
| 1636 | + * *total_nelems: 1 |
---|
| 1637 | + * *type_id: id of type if it's changed within the function, 0 if not |
---|
| 1638 | + */ |
---|
| 1639 | +static const struct btf_type * |
---|
| 1640 | +__btf_resolve_size(const struct btf *btf, const struct btf_type *type, |
---|
| 1641 | + u32 *type_size, const struct btf_type **elem_type, |
---|
| 1642 | + u32 *elem_id, u32 *total_nelems, u32 *type_id) |
---|
| 1643 | +{ |
---|
| 1644 | + const struct btf_type *array_type = NULL; |
---|
| 1645 | + const struct btf_array *array = NULL; |
---|
| 1646 | + u32 i, size, nelems = 1, id = 0; |
---|
| 1647 | + |
---|
| 1648 | + for (i = 0; i < MAX_RESOLVE_DEPTH; i++) { |
---|
| 1649 | + switch (BTF_INFO_KIND(type->info)) { |
---|
| 1650 | + /* type->size can be used */ |
---|
| 1651 | + case BTF_KIND_INT: |
---|
| 1652 | + case BTF_KIND_STRUCT: |
---|
| 1653 | + case BTF_KIND_UNION: |
---|
| 1654 | + case BTF_KIND_ENUM: |
---|
| 1655 | + size = type->size; |
---|
| 1656 | + goto resolved; |
---|
| 1657 | + |
---|
| 1658 | + case BTF_KIND_PTR: |
---|
| 1659 | + size = sizeof(void *); |
---|
| 1660 | + goto resolved; |
---|
| 1661 | + |
---|
| 1662 | + /* Modifiers */ |
---|
| 1663 | + case BTF_KIND_TYPEDEF: |
---|
| 1664 | + case BTF_KIND_VOLATILE: |
---|
| 1665 | + case BTF_KIND_CONST: |
---|
| 1666 | + case BTF_KIND_RESTRICT: |
---|
| 1667 | + id = type->type; |
---|
| 1668 | + type = btf_type_by_id(btf, type->type); |
---|
| 1669 | + break; |
---|
| 1670 | + |
---|
| 1671 | + case BTF_KIND_ARRAY: |
---|
| 1672 | + if (!array_type) |
---|
| 1673 | + array_type = type; |
---|
| 1674 | + array = btf_type_array(type); |
---|
| 1675 | + if (nelems && array->nelems > U32_MAX / nelems) |
---|
| 1676 | + return ERR_PTR(-EINVAL); |
---|
| 1677 | + nelems *= array->nelems; |
---|
| 1678 | + type = btf_type_by_id(btf, array->type); |
---|
| 1679 | + break; |
---|
| 1680 | + |
---|
| 1681 | + /* type without size */ |
---|
| 1682 | + default: |
---|
| 1683 | + return ERR_PTR(-EINVAL); |
---|
| 1684 | + } |
---|
| 1685 | + } |
---|
| 1686 | + |
---|
| 1687 | + return ERR_PTR(-EINVAL); |
---|
| 1688 | + |
---|
| 1689 | +resolved: |
---|
| 1690 | + if (nelems && size > U32_MAX / nelems) |
---|
| 1691 | + return ERR_PTR(-EINVAL); |
---|
| 1692 | + |
---|
| 1693 | + *type_size = nelems * size; |
---|
| 1694 | + if (total_nelems) |
---|
| 1695 | + *total_nelems = nelems; |
---|
| 1696 | + if (elem_type) |
---|
| 1697 | + *elem_type = type; |
---|
| 1698 | + if (elem_id) |
---|
| 1699 | + *elem_id = array ? array->type : 0; |
---|
| 1700 | + if (type_id && id) |
---|
| 1701 | + *type_id = id; |
---|
| 1702 | + |
---|
| 1703 | + return array_type ? : type; |
---|
| 1704 | +} |
---|
| 1705 | + |
---|
| 1706 | +const struct btf_type * |
---|
| 1707 | +btf_resolve_size(const struct btf *btf, const struct btf_type *type, |
---|
| 1708 | + u32 *type_size) |
---|
| 1709 | +{ |
---|
| 1710 | + return __btf_resolve_size(btf, type, type_size, NULL, NULL, NULL, NULL); |
---|
| 1711 | +} |
---|
| 1712 | + |
---|
838 | 1713 | /* The input param "type_id" must point to a needs_resolve type */ |
---|
839 | 1714 | static const struct btf_type *btf_type_id_resolve(const struct btf *btf, |
---|
840 | 1715 | u32 *type_id) |
---|
.. | .. |
---|
851 | 1726 | u32 size = 0; |
---|
852 | 1727 | |
---|
853 | 1728 | size_type = btf_type_by_id(btf, size_type_id); |
---|
854 | | - if (btf_type_is_void_or_null(size_type)) |
---|
| 1729 | + if (btf_type_nosize_or_null(size_type)) |
---|
855 | 1730 | return NULL; |
---|
856 | 1731 | |
---|
857 | 1732 | if (btf_type_has_size(size_type)) { |
---|
.. | .. |
---|
861 | 1736 | } else if (btf_type_is_ptr(size_type)) { |
---|
862 | 1737 | size = sizeof(void *); |
---|
863 | 1738 | } else { |
---|
864 | | - if (WARN_ON_ONCE(!btf_type_is_modifier(size_type))) |
---|
| 1739 | + if (WARN_ON_ONCE(!btf_type_is_modifier(size_type) && |
---|
| 1740 | + !btf_type_is_var(size_type))) |
---|
865 | 1741 | return NULL; |
---|
866 | 1742 | |
---|
867 | | - size = btf->resolved_sizes[size_type_id]; |
---|
868 | 1743 | size_type_id = btf->resolved_ids[size_type_id]; |
---|
869 | 1744 | size_type = btf_type_by_id(btf, size_type_id); |
---|
870 | | - if (btf_type_is_void(size_type)) |
---|
| 1745 | + if (btf_type_nosize_or_null(size_type)) |
---|
| 1746 | + return NULL; |
---|
| 1747 | + else if (btf_type_has_size(size_type)) |
---|
| 1748 | + size = size_type->size; |
---|
| 1749 | + else if (btf_type_is_array(size_type)) |
---|
| 1750 | + size = btf->resolved_sizes[size_type_id]; |
---|
| 1751 | + else if (btf_type_is_ptr(size_type)) |
---|
| 1752 | + size = sizeof(void *); |
---|
| 1753 | + else |
---|
871 | 1754 | return NULL; |
---|
872 | 1755 | } |
---|
873 | 1756 | |
---|
.. | .. |
---|
888 | 1771 | return -EINVAL; |
---|
889 | 1772 | } |
---|
890 | 1773 | |
---|
| 1774 | +static int btf_df_check_kflag_member(struct btf_verifier_env *env, |
---|
| 1775 | + const struct btf_type *struct_type, |
---|
| 1776 | + const struct btf_member *member, |
---|
| 1777 | + const struct btf_type *member_type) |
---|
| 1778 | +{ |
---|
| 1779 | + btf_verifier_log_basic(env, struct_type, |
---|
| 1780 | + "Unsupported check_kflag_member"); |
---|
| 1781 | + return -EINVAL; |
---|
| 1782 | +} |
---|
| 1783 | + |
---|
| 1784 | +/* Used for ptr, array and struct/union type members. |
---|
| 1785 | + * int, enum and modifier types have their specific callback functions. |
---|
| 1786 | + */ |
---|
| 1787 | +static int btf_generic_check_kflag_member(struct btf_verifier_env *env, |
---|
| 1788 | + const struct btf_type *struct_type, |
---|
| 1789 | + const struct btf_member *member, |
---|
| 1790 | + const struct btf_type *member_type) |
---|
| 1791 | +{ |
---|
| 1792 | + if (BTF_MEMBER_BITFIELD_SIZE(member->offset)) { |
---|
| 1793 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 1794 | + "Invalid member bitfield_size"); |
---|
| 1795 | + return -EINVAL; |
---|
| 1796 | + } |
---|
| 1797 | + |
---|
| 1798 | + /* bitfield size is 0, so member->offset represents bit offset only. |
---|
| 1799 | + * It is safe to call non kflag check_member variants. |
---|
| 1800 | + */ |
---|
| 1801 | + return btf_type_ops(member_type)->check_member(env, struct_type, |
---|
| 1802 | + member, |
---|
| 1803 | + member_type); |
---|
| 1804 | +} |
---|
| 1805 | + |
---|
891 | 1806 | static int btf_df_resolve(struct btf_verifier_env *env, |
---|
892 | 1807 | const struct resolve_vertex *v) |
---|
893 | 1808 | { |
---|
.. | .. |
---|
895 | 1810 | return -EINVAL; |
---|
896 | 1811 | } |
---|
897 | 1812 | |
---|
898 | | -static void btf_df_seq_show(const struct btf *btf, const struct btf_type *t, |
---|
899 | | - u32 type_id, void *data, u8 bits_offsets, |
---|
900 | | - struct seq_file *m) |
---|
| 1813 | +static void btf_df_show(const struct btf *btf, const struct btf_type *t, |
---|
| 1814 | + u32 type_id, void *data, u8 bits_offsets, |
---|
| 1815 | + struct btf_show *show) |
---|
901 | 1816 | { |
---|
902 | | - seq_printf(m, "<unsupported kind:%u>", BTF_INFO_KIND(t->info)); |
---|
| 1817 | + btf_show(show, "<unsupported kind:%u>", BTF_INFO_KIND(t->info)); |
---|
903 | 1818 | } |
---|
904 | 1819 | |
---|
905 | 1820 | static int btf_int_check_member(struct btf_verifier_env *env, |
---|
.. | .. |
---|
924 | 1839 | nr_copy_bits = BTF_INT_BITS(int_data) + |
---|
925 | 1840 | BITS_PER_BYTE_MASKED(struct_bits_off); |
---|
926 | 1841 | |
---|
927 | | - if (nr_copy_bits > BITS_PER_U64) { |
---|
| 1842 | + if (nr_copy_bits > BITS_PER_U128) { |
---|
928 | 1843 | btf_verifier_log_member(env, struct_type, member, |
---|
929 | | - "nr_copy_bits exceeds 64"); |
---|
| 1844 | + "nr_copy_bits exceeds 128"); |
---|
| 1845 | + return -EINVAL; |
---|
| 1846 | + } |
---|
| 1847 | + |
---|
| 1848 | + if (struct_size < bytes_offset || |
---|
| 1849 | + struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) { |
---|
| 1850 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 1851 | + "Member exceeds struct_size"); |
---|
| 1852 | + return -EINVAL; |
---|
| 1853 | + } |
---|
| 1854 | + |
---|
| 1855 | + return 0; |
---|
| 1856 | +} |
---|
| 1857 | + |
---|
| 1858 | +static int btf_int_check_kflag_member(struct btf_verifier_env *env, |
---|
| 1859 | + const struct btf_type *struct_type, |
---|
| 1860 | + const struct btf_member *member, |
---|
| 1861 | + const struct btf_type *member_type) |
---|
| 1862 | +{ |
---|
| 1863 | + u32 struct_bits_off, nr_bits, nr_int_data_bits, bytes_offset; |
---|
| 1864 | + u32 int_data = btf_type_int(member_type); |
---|
| 1865 | + u32 struct_size = struct_type->size; |
---|
| 1866 | + u32 nr_copy_bits; |
---|
| 1867 | + |
---|
| 1868 | + /* a regular int type is required for the kflag int member */ |
---|
| 1869 | + if (!btf_type_int_is_regular(member_type)) { |
---|
| 1870 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 1871 | + "Invalid member base type"); |
---|
| 1872 | + return -EINVAL; |
---|
| 1873 | + } |
---|
| 1874 | + |
---|
| 1875 | + /* check sanity of bitfield size */ |
---|
| 1876 | + nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset); |
---|
| 1877 | + struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset); |
---|
| 1878 | + nr_int_data_bits = BTF_INT_BITS(int_data); |
---|
| 1879 | + if (!nr_bits) { |
---|
| 1880 | + /* Not a bitfield member, member offset must be at byte |
---|
| 1881 | + * boundary. |
---|
| 1882 | + */ |
---|
| 1883 | + if (BITS_PER_BYTE_MASKED(struct_bits_off)) { |
---|
| 1884 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 1885 | + "Invalid member offset"); |
---|
| 1886 | + return -EINVAL; |
---|
| 1887 | + } |
---|
| 1888 | + |
---|
| 1889 | + nr_bits = nr_int_data_bits; |
---|
| 1890 | + } else if (nr_bits > nr_int_data_bits) { |
---|
| 1891 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 1892 | + "Invalid member bitfield_size"); |
---|
| 1893 | + return -EINVAL; |
---|
| 1894 | + } |
---|
| 1895 | + |
---|
| 1896 | + bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); |
---|
| 1897 | + nr_copy_bits = nr_bits + BITS_PER_BYTE_MASKED(struct_bits_off); |
---|
| 1898 | + if (nr_copy_bits > BITS_PER_U128) { |
---|
| 1899 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 1900 | + "nr_copy_bits exceeds 128"); |
---|
930 | 1901 | return -EINVAL; |
---|
931 | 1902 | } |
---|
932 | 1903 | |
---|
.. | .. |
---|
959 | 1930 | return -EINVAL; |
---|
960 | 1931 | } |
---|
961 | 1932 | |
---|
| 1933 | + if (btf_type_kflag(t)) { |
---|
| 1934 | + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); |
---|
| 1935 | + return -EINVAL; |
---|
| 1936 | + } |
---|
| 1937 | + |
---|
962 | 1938 | int_data = btf_type_int(t); |
---|
963 | 1939 | if (int_data & ~BTF_INT_MASK) { |
---|
964 | 1940 | btf_verifier_log_basic(env, t, "Invalid int_data:%x", |
---|
.. | .. |
---|
968 | 1944 | |
---|
969 | 1945 | nr_bits = BTF_INT_BITS(int_data) + BTF_INT_OFFSET(int_data); |
---|
970 | 1946 | |
---|
971 | | - if (nr_bits > BITS_PER_U64) { |
---|
| 1947 | + if (nr_bits > BITS_PER_U128) { |
---|
972 | 1948 | btf_verifier_log_type(env, t, "nr_bits exceeds %zu", |
---|
973 | | - BITS_PER_U64); |
---|
| 1949 | + BITS_PER_U128); |
---|
974 | 1950 | return -EINVAL; |
---|
975 | 1951 | } |
---|
976 | 1952 | |
---|
.. | .. |
---|
1011 | 1987 | btf_int_encoding_str(BTF_INT_ENCODING(int_data))); |
---|
1012 | 1988 | } |
---|
1013 | 1989 | |
---|
1014 | | -static void btf_int_bits_seq_show(const struct btf *btf, |
---|
1015 | | - const struct btf_type *t, |
---|
1016 | | - void *data, u8 bits_offset, |
---|
1017 | | - struct seq_file *m) |
---|
| 1990 | +static void btf_int128_print(struct btf_show *show, void *data) |
---|
| 1991 | +{ |
---|
| 1992 | + /* data points to a __int128 number. |
---|
| 1993 | + * Suppose |
---|
| 1994 | + * int128_num = *(__int128 *)data; |
---|
| 1995 | + * The below formulas shows what upper_num and lower_num represents: |
---|
| 1996 | + * upper_num = int128_num >> 64; |
---|
| 1997 | + * lower_num = int128_num & 0xffffffffFFFFFFFFULL; |
---|
| 1998 | + */ |
---|
| 1999 | + u64 upper_num, lower_num; |
---|
| 2000 | + |
---|
| 2001 | +#ifdef __BIG_ENDIAN_BITFIELD |
---|
| 2002 | + upper_num = *(u64 *)data; |
---|
| 2003 | + lower_num = *(u64 *)(data + 8); |
---|
| 2004 | +#else |
---|
| 2005 | + upper_num = *(u64 *)(data + 8); |
---|
| 2006 | + lower_num = *(u64 *)data; |
---|
| 2007 | +#endif |
---|
| 2008 | + if (upper_num == 0) |
---|
| 2009 | + btf_show_type_value(show, "0x%llx", lower_num); |
---|
| 2010 | + else |
---|
| 2011 | + btf_show_type_values(show, "0x%llx%016llx", upper_num, |
---|
| 2012 | + lower_num); |
---|
| 2013 | +} |
---|
| 2014 | + |
---|
| 2015 | +static void btf_int128_shift(u64 *print_num, u16 left_shift_bits, |
---|
| 2016 | + u16 right_shift_bits) |
---|
| 2017 | +{ |
---|
| 2018 | + u64 upper_num, lower_num; |
---|
| 2019 | + |
---|
| 2020 | +#ifdef __BIG_ENDIAN_BITFIELD |
---|
| 2021 | + upper_num = print_num[0]; |
---|
| 2022 | + lower_num = print_num[1]; |
---|
| 2023 | +#else |
---|
| 2024 | + upper_num = print_num[1]; |
---|
| 2025 | + lower_num = print_num[0]; |
---|
| 2026 | +#endif |
---|
| 2027 | + |
---|
| 2028 | + /* shake out un-needed bits by shift/or operations */ |
---|
| 2029 | + if (left_shift_bits >= 64) { |
---|
| 2030 | + upper_num = lower_num << (left_shift_bits - 64); |
---|
| 2031 | + lower_num = 0; |
---|
| 2032 | + } else { |
---|
| 2033 | + upper_num = (upper_num << left_shift_bits) | |
---|
| 2034 | + (lower_num >> (64 - left_shift_bits)); |
---|
| 2035 | + lower_num = lower_num << left_shift_bits; |
---|
| 2036 | + } |
---|
| 2037 | + |
---|
| 2038 | + if (right_shift_bits >= 64) { |
---|
| 2039 | + lower_num = upper_num >> (right_shift_bits - 64); |
---|
| 2040 | + upper_num = 0; |
---|
| 2041 | + } else { |
---|
| 2042 | + lower_num = (lower_num >> right_shift_bits) | |
---|
| 2043 | + (upper_num << (64 - right_shift_bits)); |
---|
| 2044 | + upper_num = upper_num >> right_shift_bits; |
---|
| 2045 | + } |
---|
| 2046 | + |
---|
| 2047 | +#ifdef __BIG_ENDIAN_BITFIELD |
---|
| 2048 | + print_num[0] = upper_num; |
---|
| 2049 | + print_num[1] = lower_num; |
---|
| 2050 | +#else |
---|
| 2051 | + print_num[0] = lower_num; |
---|
| 2052 | + print_num[1] = upper_num; |
---|
| 2053 | +#endif |
---|
| 2054 | +} |
---|
| 2055 | + |
---|
| 2056 | +static void btf_bitfield_show(void *data, u8 bits_offset, |
---|
| 2057 | + u8 nr_bits, struct btf_show *show) |
---|
1018 | 2058 | { |
---|
1019 | 2059 | u16 left_shift_bits, right_shift_bits; |
---|
1020 | | - u32 int_data = btf_type_int(t); |
---|
1021 | | - u8 nr_bits = BTF_INT_BITS(int_data); |
---|
1022 | | - u8 total_bits_offset; |
---|
1023 | 2060 | u8 nr_copy_bytes; |
---|
1024 | 2061 | u8 nr_copy_bits; |
---|
1025 | | - u64 print_num; |
---|
| 2062 | + u64 print_num[2] = {}; |
---|
1026 | 2063 | |
---|
1027 | | - /* |
---|
1028 | | - * bits_offset is at most 7. |
---|
1029 | | - * BTF_INT_OFFSET() cannot exceed 64 bits. |
---|
1030 | | - */ |
---|
1031 | | - total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data); |
---|
1032 | | - data += BITS_ROUNDDOWN_BYTES(total_bits_offset); |
---|
1033 | | - bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset); |
---|
1034 | 2064 | nr_copy_bits = nr_bits + bits_offset; |
---|
1035 | 2065 | nr_copy_bytes = BITS_ROUNDUP_BYTES(nr_copy_bits); |
---|
1036 | 2066 | |
---|
1037 | | - print_num = 0; |
---|
1038 | | - memcpy(&print_num, data, nr_copy_bytes); |
---|
| 2067 | + memcpy(print_num, data, nr_copy_bytes); |
---|
1039 | 2068 | |
---|
1040 | 2069 | #ifdef __BIG_ENDIAN_BITFIELD |
---|
1041 | 2070 | left_shift_bits = bits_offset; |
---|
1042 | 2071 | #else |
---|
1043 | | - left_shift_bits = BITS_PER_U64 - nr_copy_bits; |
---|
| 2072 | + left_shift_bits = BITS_PER_U128 - nr_copy_bits; |
---|
1044 | 2073 | #endif |
---|
1045 | | - right_shift_bits = BITS_PER_U64 - nr_bits; |
---|
| 2074 | + right_shift_bits = BITS_PER_U128 - nr_bits; |
---|
1046 | 2075 | |
---|
1047 | | - print_num <<= left_shift_bits; |
---|
1048 | | - print_num >>= right_shift_bits; |
---|
1049 | | - |
---|
1050 | | - seq_printf(m, "0x%llx", print_num); |
---|
| 2076 | + btf_int128_shift(print_num, left_shift_bits, right_shift_bits); |
---|
| 2077 | + btf_int128_print(show, print_num); |
---|
1051 | 2078 | } |
---|
1052 | 2079 | |
---|
1053 | | -static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t, |
---|
1054 | | - u32 type_id, void *data, u8 bits_offset, |
---|
1055 | | - struct seq_file *m) |
---|
| 2080 | + |
---|
| 2081 | +static void btf_int_bits_show(const struct btf *btf, |
---|
| 2082 | + const struct btf_type *t, |
---|
| 2083 | + void *data, u8 bits_offset, |
---|
| 2084 | + struct btf_show *show) |
---|
| 2085 | +{ |
---|
| 2086 | + u32 int_data = btf_type_int(t); |
---|
| 2087 | + u8 nr_bits = BTF_INT_BITS(int_data); |
---|
| 2088 | + u8 total_bits_offset; |
---|
| 2089 | + |
---|
| 2090 | + /* |
---|
| 2091 | + * bits_offset is at most 7. |
---|
| 2092 | + * BTF_INT_OFFSET() cannot exceed 128 bits. |
---|
| 2093 | + */ |
---|
| 2094 | + total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data); |
---|
| 2095 | + data += BITS_ROUNDDOWN_BYTES(total_bits_offset); |
---|
| 2096 | + bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset); |
---|
| 2097 | + btf_bitfield_show(data, bits_offset, nr_bits, show); |
---|
| 2098 | +} |
---|
| 2099 | + |
---|
| 2100 | +static void btf_int_show(const struct btf *btf, const struct btf_type *t, |
---|
| 2101 | + u32 type_id, void *data, u8 bits_offset, |
---|
| 2102 | + struct btf_show *show) |
---|
1056 | 2103 | { |
---|
1057 | 2104 | u32 int_data = btf_type_int(t); |
---|
1058 | 2105 | u8 encoding = BTF_INT_ENCODING(int_data); |
---|
1059 | 2106 | bool sign = encoding & BTF_INT_SIGNED; |
---|
1060 | 2107 | u8 nr_bits = BTF_INT_BITS(int_data); |
---|
| 2108 | + void *safe_data; |
---|
| 2109 | + |
---|
| 2110 | + safe_data = btf_show_start_type(show, t, type_id, data); |
---|
| 2111 | + if (!safe_data) |
---|
| 2112 | + return; |
---|
1061 | 2113 | |
---|
1062 | 2114 | if (bits_offset || BTF_INT_OFFSET(int_data) || |
---|
1063 | 2115 | BITS_PER_BYTE_MASKED(nr_bits)) { |
---|
1064 | | - btf_int_bits_seq_show(btf, t, data, bits_offset, m); |
---|
1065 | | - return; |
---|
| 2116 | + btf_int_bits_show(btf, t, safe_data, bits_offset, show); |
---|
| 2117 | + goto out; |
---|
1066 | 2118 | } |
---|
1067 | 2119 | |
---|
1068 | 2120 | switch (nr_bits) { |
---|
| 2121 | + case 128: |
---|
| 2122 | + btf_int128_print(show, safe_data); |
---|
| 2123 | + break; |
---|
1069 | 2124 | case 64: |
---|
1070 | 2125 | if (sign) |
---|
1071 | | - seq_printf(m, "%lld", *(s64 *)data); |
---|
| 2126 | + btf_show_type_value(show, "%lld", *(s64 *)safe_data); |
---|
1072 | 2127 | else |
---|
1073 | | - seq_printf(m, "%llu", *(u64 *)data); |
---|
| 2128 | + btf_show_type_value(show, "%llu", *(u64 *)safe_data); |
---|
1074 | 2129 | break; |
---|
1075 | 2130 | case 32: |
---|
1076 | 2131 | if (sign) |
---|
1077 | | - seq_printf(m, "%d", *(s32 *)data); |
---|
| 2132 | + btf_show_type_value(show, "%d", *(s32 *)safe_data); |
---|
1078 | 2133 | else |
---|
1079 | | - seq_printf(m, "%u", *(u32 *)data); |
---|
| 2134 | + btf_show_type_value(show, "%u", *(u32 *)safe_data); |
---|
1080 | 2135 | break; |
---|
1081 | 2136 | case 16: |
---|
1082 | 2137 | if (sign) |
---|
1083 | | - seq_printf(m, "%d", *(s16 *)data); |
---|
| 2138 | + btf_show_type_value(show, "%d", *(s16 *)safe_data); |
---|
1084 | 2139 | else |
---|
1085 | | - seq_printf(m, "%u", *(u16 *)data); |
---|
| 2140 | + btf_show_type_value(show, "%u", *(u16 *)safe_data); |
---|
1086 | 2141 | break; |
---|
1087 | 2142 | case 8: |
---|
| 2143 | + if (show->state.array_encoding == BTF_INT_CHAR) { |
---|
| 2144 | + /* check for null terminator */ |
---|
| 2145 | + if (show->state.array_terminated) |
---|
| 2146 | + break; |
---|
| 2147 | + if (*(char *)data == '\0') { |
---|
| 2148 | + show->state.array_terminated = 1; |
---|
| 2149 | + break; |
---|
| 2150 | + } |
---|
| 2151 | + if (isprint(*(char *)data)) { |
---|
| 2152 | + btf_show_type_value(show, "'%c'", |
---|
| 2153 | + *(char *)safe_data); |
---|
| 2154 | + break; |
---|
| 2155 | + } |
---|
| 2156 | + } |
---|
1088 | 2157 | if (sign) |
---|
1089 | | - seq_printf(m, "%d", *(s8 *)data); |
---|
| 2158 | + btf_show_type_value(show, "%d", *(s8 *)safe_data); |
---|
1090 | 2159 | else |
---|
1091 | | - seq_printf(m, "%u", *(u8 *)data); |
---|
| 2160 | + btf_show_type_value(show, "%u", *(u8 *)safe_data); |
---|
1092 | 2161 | break; |
---|
1093 | 2162 | default: |
---|
1094 | | - btf_int_bits_seq_show(btf, t, data, bits_offset, m); |
---|
| 2163 | + btf_int_bits_show(btf, t, safe_data, bits_offset, show); |
---|
| 2164 | + break; |
---|
1095 | 2165 | } |
---|
| 2166 | +out: |
---|
| 2167 | + btf_show_end_type(show); |
---|
1096 | 2168 | } |
---|
1097 | 2169 | |
---|
1098 | 2170 | static const struct btf_kind_operations int_ops = { |
---|
1099 | 2171 | .check_meta = btf_int_check_meta, |
---|
1100 | 2172 | .resolve = btf_df_resolve, |
---|
1101 | 2173 | .check_member = btf_int_check_member, |
---|
| 2174 | + .check_kflag_member = btf_int_check_kflag_member, |
---|
1102 | 2175 | .log_details = btf_int_log, |
---|
1103 | | - .seq_show = btf_int_seq_show, |
---|
| 2176 | + .show = btf_int_show, |
---|
1104 | 2177 | }; |
---|
1105 | 2178 | |
---|
1106 | 2179 | static int btf_modifier_check_member(struct btf_verifier_env *env, |
---|
.. | .. |
---|
1126 | 2199 | return btf_type_ops(resolved_type)->check_member(env, struct_type, |
---|
1127 | 2200 | &resolved_member, |
---|
1128 | 2201 | resolved_type); |
---|
| 2202 | +} |
---|
| 2203 | + |
---|
| 2204 | +static int btf_modifier_check_kflag_member(struct btf_verifier_env *env, |
---|
| 2205 | + const struct btf_type *struct_type, |
---|
| 2206 | + const struct btf_member *member, |
---|
| 2207 | + const struct btf_type *member_type) |
---|
| 2208 | +{ |
---|
| 2209 | + const struct btf_type *resolved_type; |
---|
| 2210 | + u32 resolved_type_id = member->type; |
---|
| 2211 | + struct btf_member resolved_member; |
---|
| 2212 | + struct btf *btf = env->btf; |
---|
| 2213 | + |
---|
| 2214 | + resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL); |
---|
| 2215 | + if (!resolved_type) { |
---|
| 2216 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 2217 | + "Invalid member"); |
---|
| 2218 | + return -EINVAL; |
---|
| 2219 | + } |
---|
| 2220 | + |
---|
| 2221 | + resolved_member = *member; |
---|
| 2222 | + resolved_member.type = resolved_type_id; |
---|
| 2223 | + |
---|
| 2224 | + return btf_type_ops(resolved_type)->check_kflag_member(env, struct_type, |
---|
| 2225 | + &resolved_member, |
---|
| 2226 | + resolved_type); |
---|
1129 | 2227 | } |
---|
1130 | 2228 | |
---|
1131 | 2229 | static int btf_ptr_check_member(struct btf_verifier_env *env, |
---|
.. | .. |
---|
1163 | 2261 | return -EINVAL; |
---|
1164 | 2262 | } |
---|
1165 | 2263 | |
---|
| 2264 | + if (btf_type_kflag(t)) { |
---|
| 2265 | + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); |
---|
| 2266 | + return -EINVAL; |
---|
| 2267 | + } |
---|
| 2268 | + |
---|
1166 | 2269 | if (!BTF_TYPE_ID_VALID(t->type)) { |
---|
1167 | 2270 | btf_verifier_log_type(env, t, "Invalid type_id"); |
---|
1168 | 2271 | return -EINVAL; |
---|
.. | .. |
---|
1196 | 2299 | const struct btf_type *next_type; |
---|
1197 | 2300 | u32 next_type_id = t->type; |
---|
1198 | 2301 | struct btf *btf = env->btf; |
---|
1199 | | - u32 next_type_size = 0; |
---|
1200 | 2302 | |
---|
1201 | 2303 | next_type = btf_type_by_id(btf, next_type_id); |
---|
1202 | | - if (!next_type) { |
---|
| 2304 | + if (!next_type || btf_type_is_resolve_source_only(next_type)) { |
---|
1203 | 2305 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
---|
1204 | 2306 | return -EINVAL; |
---|
1205 | 2307 | } |
---|
1206 | | - |
---|
1207 | | - /* "typedef void new_void", "const void"...etc */ |
---|
1208 | | - if (btf_type_is_void(next_type)) |
---|
1209 | | - goto resolved; |
---|
1210 | 2308 | |
---|
1211 | 2309 | if (!env_type_is_resolve_sink(env, next_type) && |
---|
1212 | 2310 | !env_type_is_resolved(env, next_type_id)) |
---|
.. | .. |
---|
1218 | 2316 | * save us a few type-following when we use it later (e.g. in |
---|
1219 | 2317 | * pretty print). |
---|
1220 | 2318 | */ |
---|
1221 | | - if (!btf_type_id_size(btf, &next_type_id, &next_type_size) && |
---|
1222 | | - !btf_type_is_void(btf_type_id_resolve(btf, &next_type_id))) { |
---|
| 2319 | + if (!btf_type_id_size(btf, &next_type_id, NULL)) { |
---|
| 2320 | + if (env_type_is_resolved(env, next_type_id)) |
---|
| 2321 | + next_type = btf_type_id_resolve(btf, &next_type_id); |
---|
| 2322 | + |
---|
| 2323 | + /* "typedef void new_void", "const void"...etc */ |
---|
| 2324 | + if (!btf_type_is_void(next_type) && |
---|
| 2325 | + !btf_type_is_fwd(next_type) && |
---|
| 2326 | + !btf_type_is_func_proto(next_type)) { |
---|
| 2327 | + btf_verifier_log_type(env, v->t, "Invalid type_id"); |
---|
| 2328 | + return -EINVAL; |
---|
| 2329 | + } |
---|
| 2330 | + } |
---|
| 2331 | + |
---|
| 2332 | + env_stack_pop_resolved(env, next_type_id, 0); |
---|
| 2333 | + |
---|
| 2334 | + return 0; |
---|
| 2335 | +} |
---|
| 2336 | + |
---|
| 2337 | +static int btf_var_resolve(struct btf_verifier_env *env, |
---|
| 2338 | + const struct resolve_vertex *v) |
---|
| 2339 | +{ |
---|
| 2340 | + const struct btf_type *next_type; |
---|
| 2341 | + const struct btf_type *t = v->t; |
---|
| 2342 | + u32 next_type_id = t->type; |
---|
| 2343 | + struct btf *btf = env->btf; |
---|
| 2344 | + |
---|
| 2345 | + next_type = btf_type_by_id(btf, next_type_id); |
---|
| 2346 | + if (!next_type || btf_type_is_resolve_source_only(next_type)) { |
---|
1223 | 2347 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
---|
1224 | 2348 | return -EINVAL; |
---|
1225 | 2349 | } |
---|
1226 | 2350 | |
---|
1227 | | -resolved: |
---|
1228 | | - env_stack_pop_resolved(env, next_type_id, next_type_size); |
---|
| 2351 | + if (!env_type_is_resolve_sink(env, next_type) && |
---|
| 2352 | + !env_type_is_resolved(env, next_type_id)) |
---|
| 2353 | + return env_stack_push(env, next_type, next_type_id); |
---|
| 2354 | + |
---|
| 2355 | + if (btf_type_is_modifier(next_type)) { |
---|
| 2356 | + const struct btf_type *resolved_type; |
---|
| 2357 | + u32 resolved_type_id; |
---|
| 2358 | + |
---|
| 2359 | + resolved_type_id = next_type_id; |
---|
| 2360 | + resolved_type = btf_type_id_resolve(btf, &resolved_type_id); |
---|
| 2361 | + |
---|
| 2362 | + if (btf_type_is_ptr(resolved_type) && |
---|
| 2363 | + !env_type_is_resolve_sink(env, resolved_type) && |
---|
| 2364 | + !env_type_is_resolved(env, resolved_type_id)) |
---|
| 2365 | + return env_stack_push(env, resolved_type, |
---|
| 2366 | + resolved_type_id); |
---|
| 2367 | + } |
---|
| 2368 | + |
---|
| 2369 | + /* We must resolve to something concrete at this point, no |
---|
| 2370 | + * forward types or similar that would resolve to size of |
---|
| 2371 | + * zero is allowed. |
---|
| 2372 | + */ |
---|
| 2373 | + if (!btf_type_id_size(btf, &next_type_id, NULL)) { |
---|
| 2374 | + btf_verifier_log_type(env, v->t, "Invalid type_id"); |
---|
| 2375 | + return -EINVAL; |
---|
| 2376 | + } |
---|
| 2377 | + |
---|
| 2378 | + env_stack_pop_resolved(env, next_type_id, 0); |
---|
1229 | 2379 | |
---|
1230 | 2380 | return 0; |
---|
1231 | 2381 | } |
---|
.. | .. |
---|
1237 | 2387 | const struct btf_type *t = v->t; |
---|
1238 | 2388 | u32 next_type_id = t->type; |
---|
1239 | 2389 | struct btf *btf = env->btf; |
---|
1240 | | - u32 next_type_size = 0; |
---|
1241 | 2390 | |
---|
1242 | 2391 | next_type = btf_type_by_id(btf, next_type_id); |
---|
1243 | | - if (!next_type) { |
---|
| 2392 | + if (!next_type || btf_type_is_resolve_source_only(next_type)) { |
---|
1244 | 2393 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
---|
1245 | 2394 | return -EINVAL; |
---|
1246 | 2395 | } |
---|
1247 | | - |
---|
1248 | | - /* "void *" */ |
---|
1249 | | - if (btf_type_is_void(next_type)) |
---|
1250 | | - goto resolved; |
---|
1251 | 2396 | |
---|
1252 | 2397 | if (!env_type_is_resolve_sink(env, next_type) && |
---|
1253 | 2398 | !env_type_is_resolved(env, next_type_id)) |
---|
.. | .. |
---|
1275 | 2420 | resolved_type_id); |
---|
1276 | 2421 | } |
---|
1277 | 2422 | |
---|
1278 | | - if (!btf_type_id_size(btf, &next_type_id, &next_type_size) && |
---|
1279 | | - !btf_type_is_void(btf_type_id_resolve(btf, &next_type_id))) { |
---|
1280 | | - btf_verifier_log_type(env, v->t, "Invalid type_id"); |
---|
1281 | | - return -EINVAL; |
---|
| 2423 | + if (!btf_type_id_size(btf, &next_type_id, NULL)) { |
---|
| 2424 | + if (env_type_is_resolved(env, next_type_id)) |
---|
| 2425 | + next_type = btf_type_id_resolve(btf, &next_type_id); |
---|
| 2426 | + |
---|
| 2427 | + if (!btf_type_is_void(next_type) && |
---|
| 2428 | + !btf_type_is_fwd(next_type) && |
---|
| 2429 | + !btf_type_is_func_proto(next_type)) { |
---|
| 2430 | + btf_verifier_log_type(env, v->t, "Invalid type_id"); |
---|
| 2431 | + return -EINVAL; |
---|
| 2432 | + } |
---|
1282 | 2433 | } |
---|
1283 | 2434 | |
---|
1284 | | -resolved: |
---|
1285 | 2435 | env_stack_pop_resolved(env, next_type_id, 0); |
---|
1286 | 2436 | |
---|
1287 | 2437 | return 0; |
---|
1288 | 2438 | } |
---|
1289 | 2439 | |
---|
1290 | | -static void btf_modifier_seq_show(const struct btf *btf, |
---|
1291 | | - const struct btf_type *t, |
---|
1292 | | - u32 type_id, void *data, |
---|
1293 | | - u8 bits_offset, struct seq_file *m) |
---|
| 2440 | +static void btf_modifier_show(const struct btf *btf, |
---|
| 2441 | + const struct btf_type *t, |
---|
| 2442 | + u32 type_id, void *data, |
---|
| 2443 | + u8 bits_offset, struct btf_show *show) |
---|
| 2444 | +{ |
---|
| 2445 | + if (btf->resolved_ids) |
---|
| 2446 | + t = btf_type_id_resolve(btf, &type_id); |
---|
| 2447 | + else |
---|
| 2448 | + t = btf_type_skip_modifiers(btf, type_id, NULL); |
---|
| 2449 | + |
---|
| 2450 | + btf_type_ops(t)->show(btf, t, type_id, data, bits_offset, show); |
---|
| 2451 | +} |
---|
| 2452 | + |
---|
| 2453 | +static void btf_var_show(const struct btf *btf, const struct btf_type *t, |
---|
| 2454 | + u32 type_id, void *data, u8 bits_offset, |
---|
| 2455 | + struct btf_show *show) |
---|
1294 | 2456 | { |
---|
1295 | 2457 | t = btf_type_id_resolve(btf, &type_id); |
---|
1296 | 2458 | |
---|
1297 | | - btf_type_ops(t)->seq_show(btf, t, type_id, data, bits_offset, m); |
---|
| 2459 | + btf_type_ops(t)->show(btf, t, type_id, data, bits_offset, show); |
---|
1298 | 2460 | } |
---|
1299 | 2461 | |
---|
1300 | | -static void btf_ptr_seq_show(const struct btf *btf, const struct btf_type *t, |
---|
1301 | | - u32 type_id, void *data, u8 bits_offset, |
---|
1302 | | - struct seq_file *m) |
---|
| 2462 | +static void btf_ptr_show(const struct btf *btf, const struct btf_type *t, |
---|
| 2463 | + u32 type_id, void *data, u8 bits_offset, |
---|
| 2464 | + struct btf_show *show) |
---|
1303 | 2465 | { |
---|
1304 | | - /* It is a hashed value */ |
---|
1305 | | - seq_printf(m, "%p", *(void **)data); |
---|
| 2466 | + void *safe_data; |
---|
| 2467 | + |
---|
| 2468 | + safe_data = btf_show_start_type(show, t, type_id, data); |
---|
| 2469 | + if (!safe_data) |
---|
| 2470 | + return; |
---|
| 2471 | + |
---|
| 2472 | + /* It is a hashed value unless BTF_SHOW_PTR_RAW is specified */ |
---|
| 2473 | + if (show->flags & BTF_SHOW_PTR_RAW) |
---|
| 2474 | + btf_show_type_value(show, "0x%px", *(void **)safe_data); |
---|
| 2475 | + else |
---|
| 2476 | + btf_show_type_value(show, "0x%p", *(void **)safe_data); |
---|
| 2477 | + btf_show_end_type(show); |
---|
1306 | 2478 | } |
---|
1307 | 2479 | |
---|
1308 | 2480 | static void btf_ref_type_log(struct btf_verifier_env *env, |
---|
.. | .. |
---|
1315 | 2487 | .check_meta = btf_ref_type_check_meta, |
---|
1316 | 2488 | .resolve = btf_modifier_resolve, |
---|
1317 | 2489 | .check_member = btf_modifier_check_member, |
---|
| 2490 | + .check_kflag_member = btf_modifier_check_kflag_member, |
---|
1318 | 2491 | .log_details = btf_ref_type_log, |
---|
1319 | | - .seq_show = btf_modifier_seq_show, |
---|
| 2492 | + .show = btf_modifier_show, |
---|
1320 | 2493 | }; |
---|
1321 | 2494 | |
---|
1322 | 2495 | static struct btf_kind_operations ptr_ops = { |
---|
1323 | 2496 | .check_meta = btf_ref_type_check_meta, |
---|
1324 | 2497 | .resolve = btf_ptr_resolve, |
---|
1325 | 2498 | .check_member = btf_ptr_check_member, |
---|
| 2499 | + .check_kflag_member = btf_generic_check_kflag_member, |
---|
1326 | 2500 | .log_details = btf_ref_type_log, |
---|
1327 | | - .seq_show = btf_ptr_seq_show, |
---|
| 2501 | + .show = btf_ptr_show, |
---|
1328 | 2502 | }; |
---|
1329 | 2503 | |
---|
1330 | 2504 | static s32 btf_fwd_check_meta(struct btf_verifier_env *env, |
---|
.. | .. |
---|
1353 | 2527 | return 0; |
---|
1354 | 2528 | } |
---|
1355 | 2529 | |
---|
| 2530 | +static void btf_fwd_type_log(struct btf_verifier_env *env, |
---|
| 2531 | + const struct btf_type *t) |
---|
| 2532 | +{ |
---|
| 2533 | + btf_verifier_log(env, "%s", btf_type_kflag(t) ? "union" : "struct"); |
---|
| 2534 | +} |
---|
| 2535 | + |
---|
1356 | 2536 | static struct btf_kind_operations fwd_ops = { |
---|
1357 | 2537 | .check_meta = btf_fwd_check_meta, |
---|
1358 | 2538 | .resolve = btf_df_resolve, |
---|
1359 | 2539 | .check_member = btf_df_check_member, |
---|
1360 | | - .log_details = btf_ref_type_log, |
---|
1361 | | - .seq_show = btf_df_seq_show, |
---|
| 2540 | + .check_kflag_member = btf_df_check_kflag_member, |
---|
| 2541 | + .log_details = btf_fwd_type_log, |
---|
| 2542 | + .show = btf_df_show, |
---|
1362 | 2543 | }; |
---|
1363 | 2544 | |
---|
1364 | 2545 | static int btf_array_check_member(struct btf_verifier_env *env, |
---|
.. | .. |
---|
1415 | 2596 | return -EINVAL; |
---|
1416 | 2597 | } |
---|
1417 | 2598 | |
---|
| 2599 | + if (btf_type_kflag(t)) { |
---|
| 2600 | + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); |
---|
| 2601 | + return -EINVAL; |
---|
| 2602 | + } |
---|
| 2603 | + |
---|
1418 | 2604 | if (t->size) { |
---|
1419 | 2605 | btf_verifier_log_type(env, t, "size != 0"); |
---|
1420 | 2606 | return -EINVAL; |
---|
.. | .. |
---|
1450 | 2636 | /* Check array->index_type */ |
---|
1451 | 2637 | index_type_id = array->index_type; |
---|
1452 | 2638 | index_type = btf_type_by_id(btf, index_type_id); |
---|
1453 | | - if (btf_type_is_void_or_null(index_type)) { |
---|
| 2639 | + if (btf_type_nosize_or_null(index_type) || |
---|
| 2640 | + btf_type_is_resolve_source_only(index_type)) { |
---|
1454 | 2641 | btf_verifier_log_type(env, v->t, "Invalid index"); |
---|
1455 | 2642 | return -EINVAL; |
---|
1456 | 2643 | } |
---|
.. | .. |
---|
1469 | 2656 | /* Check array->type */ |
---|
1470 | 2657 | elem_type_id = array->type; |
---|
1471 | 2658 | elem_type = btf_type_by_id(btf, elem_type_id); |
---|
1472 | | - if (btf_type_is_void_or_null(elem_type)) { |
---|
| 2659 | + if (btf_type_nosize_or_null(elem_type) || |
---|
| 2660 | + btf_type_is_resolve_source_only(elem_type)) { |
---|
1473 | 2661 | btf_verifier_log_type(env, v->t, |
---|
1474 | 2662 | "Invalid elem"); |
---|
1475 | 2663 | return -EINVAL; |
---|
.. | .. |
---|
1510 | 2698 | array->type, array->index_type, array->nelems); |
---|
1511 | 2699 | } |
---|
1512 | 2700 | |
---|
1513 | | -static void btf_array_seq_show(const struct btf *btf, const struct btf_type *t, |
---|
1514 | | - u32 type_id, void *data, u8 bits_offset, |
---|
1515 | | - struct seq_file *m) |
---|
| 2701 | +static void __btf_array_show(const struct btf *btf, const struct btf_type *t, |
---|
| 2702 | + u32 type_id, void *data, u8 bits_offset, |
---|
| 2703 | + struct btf_show *show) |
---|
1516 | 2704 | { |
---|
1517 | 2705 | const struct btf_array *array = btf_type_array(t); |
---|
1518 | 2706 | const struct btf_kind_operations *elem_ops; |
---|
1519 | 2707 | const struct btf_type *elem_type; |
---|
1520 | | - u32 i, elem_size, elem_type_id; |
---|
| 2708 | + u32 i, elem_size = 0, elem_type_id; |
---|
| 2709 | + u16 encoding = 0; |
---|
1521 | 2710 | |
---|
1522 | 2711 | elem_type_id = array->type; |
---|
1523 | | - elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size); |
---|
1524 | | - elem_ops = btf_type_ops(elem_type); |
---|
1525 | | - seq_puts(m, "["); |
---|
1526 | | - for (i = 0; i < array->nelems; i++) { |
---|
1527 | | - if (i) |
---|
1528 | | - seq_puts(m, ","); |
---|
| 2712 | + elem_type = btf_type_skip_modifiers(btf, elem_type_id, NULL); |
---|
| 2713 | + if (elem_type && btf_type_has_size(elem_type)) |
---|
| 2714 | + elem_size = elem_type->size; |
---|
1529 | 2715 | |
---|
1530 | | - elem_ops->seq_show(btf, elem_type, elem_type_id, data, |
---|
1531 | | - bits_offset, m); |
---|
1532 | | - data += elem_size; |
---|
| 2716 | + if (elem_type && btf_type_is_int(elem_type)) { |
---|
| 2717 | + u32 int_type = btf_type_int(elem_type); |
---|
| 2718 | + |
---|
| 2719 | + encoding = BTF_INT_ENCODING(int_type); |
---|
| 2720 | + |
---|
| 2721 | + /* |
---|
| 2722 | + * BTF_INT_CHAR encoding never seems to be set for |
---|
| 2723 | + * char arrays, so if size is 1 and element is |
---|
| 2724 | + * printable as a char, we'll do that. |
---|
| 2725 | + */ |
---|
| 2726 | + if (elem_size == 1) |
---|
| 2727 | + encoding = BTF_INT_CHAR; |
---|
1533 | 2728 | } |
---|
1534 | | - seq_puts(m, "]"); |
---|
| 2729 | + |
---|
| 2730 | + if (!btf_show_start_array_type(show, t, type_id, encoding, data)) |
---|
| 2731 | + return; |
---|
| 2732 | + |
---|
| 2733 | + if (!elem_type) |
---|
| 2734 | + goto out; |
---|
| 2735 | + elem_ops = btf_type_ops(elem_type); |
---|
| 2736 | + |
---|
| 2737 | + for (i = 0; i < array->nelems; i++) { |
---|
| 2738 | + |
---|
| 2739 | + btf_show_start_array_member(show); |
---|
| 2740 | + |
---|
| 2741 | + elem_ops->show(btf, elem_type, elem_type_id, data, |
---|
| 2742 | + bits_offset, show); |
---|
| 2743 | + data += elem_size; |
---|
| 2744 | + |
---|
| 2745 | + btf_show_end_array_member(show); |
---|
| 2746 | + |
---|
| 2747 | + if (show->state.array_terminated) |
---|
| 2748 | + break; |
---|
| 2749 | + } |
---|
| 2750 | +out: |
---|
| 2751 | + btf_show_end_array_type(show); |
---|
| 2752 | +} |
---|
| 2753 | + |
---|
| 2754 | +static void btf_array_show(const struct btf *btf, const struct btf_type *t, |
---|
| 2755 | + u32 type_id, void *data, u8 bits_offset, |
---|
| 2756 | + struct btf_show *show) |
---|
| 2757 | +{ |
---|
| 2758 | + const struct btf_member *m = show->state.member; |
---|
| 2759 | + |
---|
| 2760 | + /* |
---|
| 2761 | + * First check if any members would be shown (are non-zero). |
---|
| 2762 | + * See comments above "struct btf_show" definition for more |
---|
| 2763 | + * details on how this works at a high-level. |
---|
| 2764 | + */ |
---|
| 2765 | + if (show->state.depth > 0 && !(show->flags & BTF_SHOW_ZERO)) { |
---|
| 2766 | + if (!show->state.depth_check) { |
---|
| 2767 | + show->state.depth_check = show->state.depth + 1; |
---|
| 2768 | + show->state.depth_to_show = 0; |
---|
| 2769 | + } |
---|
| 2770 | + __btf_array_show(btf, t, type_id, data, bits_offset, show); |
---|
| 2771 | + show->state.member = m; |
---|
| 2772 | + |
---|
| 2773 | + if (show->state.depth_check != show->state.depth + 1) |
---|
| 2774 | + return; |
---|
| 2775 | + show->state.depth_check = 0; |
---|
| 2776 | + |
---|
| 2777 | + if (show->state.depth_to_show <= show->state.depth) |
---|
| 2778 | + return; |
---|
| 2779 | + /* |
---|
| 2780 | + * Reaching here indicates we have recursed and found |
---|
| 2781 | + * non-zero array member(s). |
---|
| 2782 | + */ |
---|
| 2783 | + } |
---|
| 2784 | + __btf_array_show(btf, t, type_id, data, bits_offset, show); |
---|
1535 | 2785 | } |
---|
1536 | 2786 | |
---|
1537 | 2787 | static struct btf_kind_operations array_ops = { |
---|
1538 | 2788 | .check_meta = btf_array_check_meta, |
---|
1539 | 2789 | .resolve = btf_array_resolve, |
---|
1540 | 2790 | .check_member = btf_array_check_member, |
---|
| 2791 | + .check_kflag_member = btf_generic_check_kflag_member, |
---|
1541 | 2792 | .log_details = btf_array_log, |
---|
1542 | | - .seq_show = btf_array_seq_show, |
---|
| 2793 | + .show = btf_array_show, |
---|
1543 | 2794 | }; |
---|
1544 | 2795 | |
---|
1545 | 2796 | static int btf_struct_check_member(struct btf_verifier_env *env, |
---|
.. | .. |
---|
1576 | 2827 | u32 meta_needed, last_offset; |
---|
1577 | 2828 | struct btf *btf = env->btf; |
---|
1578 | 2829 | u32 struct_size = t->size; |
---|
| 2830 | + u32 offset; |
---|
1579 | 2831 | u16 i; |
---|
1580 | 2832 | |
---|
1581 | 2833 | meta_needed = btf_type_vlen(t) * sizeof(*member); |
---|
.. | .. |
---|
1617 | 2869 | return -EINVAL; |
---|
1618 | 2870 | } |
---|
1619 | 2871 | |
---|
1620 | | - if (is_union && member->offset) { |
---|
| 2872 | + offset = btf_member_bit_offset(t, member); |
---|
| 2873 | + if (is_union && offset) { |
---|
1621 | 2874 | btf_verifier_log_member(env, t, member, |
---|
1622 | 2875 | "Invalid member bits_offset"); |
---|
1623 | 2876 | return -EINVAL; |
---|
.. | .. |
---|
1627 | 2880 | * ">" instead of ">=" because the last member could be |
---|
1628 | 2881 | * "char a[0];" |
---|
1629 | 2882 | */ |
---|
1630 | | - if (last_offset > member->offset) { |
---|
| 2883 | + if (last_offset > offset) { |
---|
1631 | 2884 | btf_verifier_log_member(env, t, member, |
---|
1632 | 2885 | "Invalid member bits_offset"); |
---|
1633 | 2886 | return -EINVAL; |
---|
1634 | 2887 | } |
---|
1635 | 2888 | |
---|
1636 | | - if (BITS_ROUNDUP_BYTES(member->offset) > struct_size) { |
---|
| 2889 | + if (BITS_ROUNDUP_BYTES(offset) > struct_size) { |
---|
1637 | 2890 | btf_verifier_log_member(env, t, member, |
---|
1638 | | - "Memmber bits_offset exceeds its struct size"); |
---|
| 2891 | + "Member bits_offset exceeds its struct size"); |
---|
1639 | 2892 | return -EINVAL; |
---|
1640 | 2893 | } |
---|
1641 | 2894 | |
---|
1642 | 2895 | btf_verifier_log_member(env, t, member, NULL); |
---|
1643 | | - last_offset = member->offset; |
---|
| 2896 | + last_offset = offset; |
---|
1644 | 2897 | } |
---|
1645 | 2898 | |
---|
1646 | 2899 | return meta_needed; |
---|
.. | .. |
---|
1660 | 2913 | if (v->next_member) { |
---|
1661 | 2914 | const struct btf_type *last_member_type; |
---|
1662 | 2915 | const struct btf_member *last_member; |
---|
1663 | | - u16 last_member_type_id; |
---|
| 2916 | + u32 last_member_type_id; |
---|
1664 | 2917 | |
---|
1665 | 2918 | last_member = btf_type_member(v->t) + v->next_member - 1; |
---|
1666 | 2919 | last_member_type_id = last_member->type; |
---|
.. | .. |
---|
1670 | 2923 | |
---|
1671 | 2924 | last_member_type = btf_type_by_id(env->btf, |
---|
1672 | 2925 | last_member_type_id); |
---|
1673 | | - err = btf_type_ops(last_member_type)->check_member(env, v->t, |
---|
1674 | | - last_member, |
---|
1675 | | - last_member_type); |
---|
| 2926 | + if (btf_type_kflag(v->t)) |
---|
| 2927 | + err = btf_type_ops(last_member_type)->check_kflag_member(env, v->t, |
---|
| 2928 | + last_member, |
---|
| 2929 | + last_member_type); |
---|
| 2930 | + else |
---|
| 2931 | + err = btf_type_ops(last_member_type)->check_member(env, v->t, |
---|
| 2932 | + last_member, |
---|
| 2933 | + last_member_type); |
---|
1676 | 2934 | if (err) |
---|
1677 | 2935 | return err; |
---|
1678 | 2936 | } |
---|
.. | .. |
---|
1682 | 2940 | const struct btf_type *member_type = btf_type_by_id(env->btf, |
---|
1683 | 2941 | member_type_id); |
---|
1684 | 2942 | |
---|
1685 | | - if (btf_type_is_void_or_null(member_type)) { |
---|
| 2943 | + if (btf_type_nosize_or_null(member_type) || |
---|
| 2944 | + btf_type_is_resolve_source_only(member_type)) { |
---|
1686 | 2945 | btf_verifier_log_member(env, v->t, member, |
---|
1687 | 2946 | "Invalid member"); |
---|
1688 | 2947 | return -EINVAL; |
---|
.. | .. |
---|
1694 | 2953 | return env_stack_push(env, member_type, member_type_id); |
---|
1695 | 2954 | } |
---|
1696 | 2955 | |
---|
1697 | | - err = btf_type_ops(member_type)->check_member(env, v->t, |
---|
1698 | | - member, |
---|
1699 | | - member_type); |
---|
| 2956 | + if (btf_type_kflag(v->t)) |
---|
| 2957 | + err = btf_type_ops(member_type)->check_kflag_member(env, v->t, |
---|
| 2958 | + member, |
---|
| 2959 | + member_type); |
---|
| 2960 | + else |
---|
| 2961 | + err = btf_type_ops(member_type)->check_member(env, v->t, |
---|
| 2962 | + member, |
---|
| 2963 | + member_type); |
---|
1700 | 2964 | if (err) |
---|
1701 | 2965 | return err; |
---|
1702 | 2966 | } |
---|
.. | .. |
---|
1712 | 2976 | btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); |
---|
1713 | 2977 | } |
---|
1714 | 2978 | |
---|
1715 | | -static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t, |
---|
1716 | | - u32 type_id, void *data, u8 bits_offset, |
---|
1717 | | - struct seq_file *m) |
---|
| 2979 | +/* find 'struct bpf_spin_lock' in map value. |
---|
| 2980 | + * return >= 0 offset if found |
---|
| 2981 | + * and < 0 in case of error |
---|
| 2982 | + */ |
---|
| 2983 | +int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t) |
---|
1718 | 2984 | { |
---|
1719 | | - const char *seq = BTF_INFO_KIND(t->info) == BTF_KIND_UNION ? "|" : ","; |
---|
1720 | 2985 | const struct btf_member *member; |
---|
| 2986 | + u32 i, off = -ENOENT; |
---|
| 2987 | + |
---|
| 2988 | + if (!__btf_type_is_struct(t)) |
---|
| 2989 | + return -EINVAL; |
---|
| 2990 | + |
---|
| 2991 | + for_each_member(i, t, member) { |
---|
| 2992 | + const struct btf_type *member_type = btf_type_by_id(btf, |
---|
| 2993 | + member->type); |
---|
| 2994 | + if (!__btf_type_is_struct(member_type)) |
---|
| 2995 | + continue; |
---|
| 2996 | + if (member_type->size != sizeof(struct bpf_spin_lock)) |
---|
| 2997 | + continue; |
---|
| 2998 | + if (strcmp(__btf_name_by_offset(btf, member_type->name_off), |
---|
| 2999 | + "bpf_spin_lock")) |
---|
| 3000 | + continue; |
---|
| 3001 | + if (off != -ENOENT) |
---|
| 3002 | + /* only one 'struct bpf_spin_lock' is allowed */ |
---|
| 3003 | + return -E2BIG; |
---|
| 3004 | + off = btf_member_bit_offset(t, member); |
---|
| 3005 | + if (off % 8) |
---|
| 3006 | + /* valid C code cannot generate such BTF */ |
---|
| 3007 | + return -EINVAL; |
---|
| 3008 | + off /= 8; |
---|
| 3009 | + if (off % __alignof__(struct bpf_spin_lock)) |
---|
| 3010 | + /* valid struct bpf_spin_lock will be 4 byte aligned */ |
---|
| 3011 | + return -EINVAL; |
---|
| 3012 | + } |
---|
| 3013 | + return off; |
---|
| 3014 | +} |
---|
| 3015 | + |
---|
| 3016 | +static void __btf_struct_show(const struct btf *btf, const struct btf_type *t, |
---|
| 3017 | + u32 type_id, void *data, u8 bits_offset, |
---|
| 3018 | + struct btf_show *show) |
---|
| 3019 | +{ |
---|
| 3020 | + const struct btf_member *member; |
---|
| 3021 | + void *safe_data; |
---|
1721 | 3022 | u32 i; |
---|
1722 | 3023 | |
---|
1723 | | - seq_puts(m, "{"); |
---|
| 3024 | + safe_data = btf_show_start_struct_type(show, t, type_id, data); |
---|
| 3025 | + if (!safe_data) |
---|
| 3026 | + return; |
---|
| 3027 | + |
---|
1724 | 3028 | for_each_member(i, t, member) { |
---|
1725 | 3029 | const struct btf_type *member_type = btf_type_by_id(btf, |
---|
1726 | 3030 | member->type); |
---|
1727 | | - u32 member_offset = member->offset; |
---|
1728 | | - u32 bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset); |
---|
1729 | | - u8 bits8_offset = BITS_PER_BYTE_MASKED(member_offset); |
---|
1730 | 3031 | const struct btf_kind_operations *ops; |
---|
| 3032 | + u32 member_offset, bitfield_size; |
---|
| 3033 | + u32 bytes_offset; |
---|
| 3034 | + u8 bits8_offset; |
---|
1731 | 3035 | |
---|
1732 | | - if (i) |
---|
1733 | | - seq_puts(m, seq); |
---|
| 3036 | + btf_show_start_member(show, member); |
---|
1734 | 3037 | |
---|
1735 | | - ops = btf_type_ops(member_type); |
---|
1736 | | - ops->seq_show(btf, member_type, member->type, |
---|
1737 | | - data + bytes_offset, bits8_offset, m); |
---|
| 3038 | + member_offset = btf_member_bit_offset(t, member); |
---|
| 3039 | + bitfield_size = btf_member_bitfield_size(t, member); |
---|
| 3040 | + bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset); |
---|
| 3041 | + bits8_offset = BITS_PER_BYTE_MASKED(member_offset); |
---|
| 3042 | + if (bitfield_size) { |
---|
| 3043 | + safe_data = btf_show_start_type(show, member_type, |
---|
| 3044 | + member->type, |
---|
| 3045 | + data + bytes_offset); |
---|
| 3046 | + if (safe_data) |
---|
| 3047 | + btf_bitfield_show(safe_data, |
---|
| 3048 | + bits8_offset, |
---|
| 3049 | + bitfield_size, show); |
---|
| 3050 | + btf_show_end_type(show); |
---|
| 3051 | + } else { |
---|
| 3052 | + ops = btf_type_ops(member_type); |
---|
| 3053 | + ops->show(btf, member_type, member->type, |
---|
| 3054 | + data + bytes_offset, bits8_offset, show); |
---|
| 3055 | + } |
---|
| 3056 | + |
---|
| 3057 | + btf_show_end_member(show); |
---|
1738 | 3058 | } |
---|
1739 | | - seq_puts(m, "}"); |
---|
| 3059 | + |
---|
| 3060 | + btf_show_end_struct_type(show); |
---|
| 3061 | +} |
---|
| 3062 | + |
---|
| 3063 | +static void btf_struct_show(const struct btf *btf, const struct btf_type *t, |
---|
| 3064 | + u32 type_id, void *data, u8 bits_offset, |
---|
| 3065 | + struct btf_show *show) |
---|
| 3066 | +{ |
---|
| 3067 | + const struct btf_member *m = show->state.member; |
---|
| 3068 | + |
---|
| 3069 | + /* |
---|
| 3070 | + * First check if any members would be shown (are non-zero). |
---|
| 3071 | + * See comments above "struct btf_show" definition for more |
---|
| 3072 | + * details on how this works at a high-level. |
---|
| 3073 | + */ |
---|
| 3074 | + if (show->state.depth > 0 && !(show->flags & BTF_SHOW_ZERO)) { |
---|
| 3075 | + if (!show->state.depth_check) { |
---|
| 3076 | + show->state.depth_check = show->state.depth + 1; |
---|
| 3077 | + show->state.depth_to_show = 0; |
---|
| 3078 | + } |
---|
| 3079 | + __btf_struct_show(btf, t, type_id, data, bits_offset, show); |
---|
| 3080 | + /* Restore saved member data here */ |
---|
| 3081 | + show->state.member = m; |
---|
| 3082 | + if (show->state.depth_check != show->state.depth + 1) |
---|
| 3083 | + return; |
---|
| 3084 | + show->state.depth_check = 0; |
---|
| 3085 | + |
---|
| 3086 | + if (show->state.depth_to_show <= show->state.depth) |
---|
| 3087 | + return; |
---|
| 3088 | + /* |
---|
| 3089 | + * Reaching here indicates we have recursed and found |
---|
| 3090 | + * non-zero child values. |
---|
| 3091 | + */ |
---|
| 3092 | + } |
---|
| 3093 | + |
---|
| 3094 | + __btf_struct_show(btf, t, type_id, data, bits_offset, show); |
---|
1740 | 3095 | } |
---|
1741 | 3096 | |
---|
1742 | 3097 | static struct btf_kind_operations struct_ops = { |
---|
1743 | 3098 | .check_meta = btf_struct_check_meta, |
---|
1744 | 3099 | .resolve = btf_struct_resolve, |
---|
1745 | 3100 | .check_member = btf_struct_check_member, |
---|
| 3101 | + .check_kflag_member = btf_generic_check_kflag_member, |
---|
1746 | 3102 | .log_details = btf_struct_log, |
---|
1747 | | - .seq_show = btf_struct_seq_show, |
---|
| 3103 | + .show = btf_struct_show, |
---|
1748 | 3104 | }; |
---|
1749 | 3105 | |
---|
1750 | 3106 | static int btf_enum_check_member(struct btf_verifier_env *env, |
---|
.. | .. |
---|
1772 | 3128 | return 0; |
---|
1773 | 3129 | } |
---|
1774 | 3130 | |
---|
| 3131 | +static int btf_enum_check_kflag_member(struct btf_verifier_env *env, |
---|
| 3132 | + const struct btf_type *struct_type, |
---|
| 3133 | + const struct btf_member *member, |
---|
| 3134 | + const struct btf_type *member_type) |
---|
| 3135 | +{ |
---|
| 3136 | + u32 struct_bits_off, nr_bits, bytes_end, struct_size; |
---|
| 3137 | + u32 int_bitsize = sizeof(int) * BITS_PER_BYTE; |
---|
| 3138 | + |
---|
| 3139 | + struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset); |
---|
| 3140 | + nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset); |
---|
| 3141 | + if (!nr_bits) { |
---|
| 3142 | + if (BITS_PER_BYTE_MASKED(struct_bits_off)) { |
---|
| 3143 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 3144 | + "Member is not byte aligned"); |
---|
| 3145 | + return -EINVAL; |
---|
| 3146 | + } |
---|
| 3147 | + |
---|
| 3148 | + nr_bits = int_bitsize; |
---|
| 3149 | + } else if (nr_bits > int_bitsize) { |
---|
| 3150 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 3151 | + "Invalid member bitfield_size"); |
---|
| 3152 | + return -EINVAL; |
---|
| 3153 | + } |
---|
| 3154 | + |
---|
| 3155 | + struct_size = struct_type->size; |
---|
| 3156 | + bytes_end = BITS_ROUNDUP_BYTES(struct_bits_off + nr_bits); |
---|
| 3157 | + if (struct_size < bytes_end) { |
---|
| 3158 | + btf_verifier_log_member(env, struct_type, member, |
---|
| 3159 | + "Member exceeds struct_size"); |
---|
| 3160 | + return -EINVAL; |
---|
| 3161 | + } |
---|
| 3162 | + |
---|
| 3163 | + return 0; |
---|
| 3164 | +} |
---|
| 3165 | + |
---|
1775 | 3166 | static s32 btf_enum_check_meta(struct btf_verifier_env *env, |
---|
1776 | 3167 | const struct btf_type *t, |
---|
1777 | 3168 | u32 meta_left) |
---|
.. | .. |
---|
1791 | 3182 | return -EINVAL; |
---|
1792 | 3183 | } |
---|
1793 | 3184 | |
---|
1794 | | - if (t->size != sizeof(int)) { |
---|
1795 | | - btf_verifier_log_type(env, t, "Expected size:%zu", |
---|
1796 | | - sizeof(int)); |
---|
| 3185 | + if (btf_type_kflag(t)) { |
---|
| 3186 | + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); |
---|
| 3187 | + return -EINVAL; |
---|
| 3188 | + } |
---|
| 3189 | + |
---|
| 3190 | + if (t->size > 8 || !is_power_of_2(t->size)) { |
---|
| 3191 | + btf_verifier_log_type(env, t, "Unexpected size"); |
---|
1797 | 3192 | return -EINVAL; |
---|
1798 | 3193 | } |
---|
1799 | 3194 | |
---|
.. | .. |
---|
1820 | 3215 | return -EINVAL; |
---|
1821 | 3216 | } |
---|
1822 | 3217 | |
---|
1823 | | - |
---|
| 3218 | + if (env->log.level == BPF_LOG_KERNEL) |
---|
| 3219 | + continue; |
---|
1824 | 3220 | btf_verifier_log(env, "\t%s val=%d\n", |
---|
1825 | | - btf_name_by_offset(btf, enums[i].name_off), |
---|
| 3221 | + __btf_name_by_offset(btf, enums[i].name_off), |
---|
1826 | 3222 | enums[i].val); |
---|
1827 | 3223 | } |
---|
1828 | 3224 | |
---|
.. | .. |
---|
1835 | 3231 | btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); |
---|
1836 | 3232 | } |
---|
1837 | 3233 | |
---|
1838 | | -static void btf_enum_seq_show(const struct btf *btf, const struct btf_type *t, |
---|
1839 | | - u32 type_id, void *data, u8 bits_offset, |
---|
1840 | | - struct seq_file *m) |
---|
| 3234 | +static void btf_enum_show(const struct btf *btf, const struct btf_type *t, |
---|
| 3235 | + u32 type_id, void *data, u8 bits_offset, |
---|
| 3236 | + struct btf_show *show) |
---|
1841 | 3237 | { |
---|
1842 | 3238 | const struct btf_enum *enums = btf_type_enum(t); |
---|
1843 | 3239 | u32 i, nr_enums = btf_type_vlen(t); |
---|
1844 | | - int v = *(int *)data; |
---|
| 3240 | + void *safe_data; |
---|
| 3241 | + int v; |
---|
| 3242 | + |
---|
| 3243 | + safe_data = btf_show_start_type(show, t, type_id, data); |
---|
| 3244 | + if (!safe_data) |
---|
| 3245 | + return; |
---|
| 3246 | + |
---|
| 3247 | + v = *(int *)safe_data; |
---|
1845 | 3248 | |
---|
1846 | 3249 | for (i = 0; i < nr_enums; i++) { |
---|
1847 | | - if (v == enums[i].val) { |
---|
1848 | | - seq_printf(m, "%s", |
---|
1849 | | - btf_name_by_offset(btf, enums[i].name_off)); |
---|
1850 | | - return; |
---|
1851 | | - } |
---|
| 3250 | + if (v != enums[i].val) |
---|
| 3251 | + continue; |
---|
| 3252 | + |
---|
| 3253 | + btf_show_type_value(show, "%s", |
---|
| 3254 | + __btf_name_by_offset(btf, |
---|
| 3255 | + enums[i].name_off)); |
---|
| 3256 | + |
---|
| 3257 | + btf_show_end_type(show); |
---|
| 3258 | + return; |
---|
1852 | 3259 | } |
---|
1853 | 3260 | |
---|
1854 | | - seq_printf(m, "%d", v); |
---|
| 3261 | + btf_show_type_value(show, "%d", v); |
---|
| 3262 | + btf_show_end_type(show); |
---|
1855 | 3263 | } |
---|
1856 | 3264 | |
---|
1857 | 3265 | static struct btf_kind_operations enum_ops = { |
---|
1858 | 3266 | .check_meta = btf_enum_check_meta, |
---|
1859 | 3267 | .resolve = btf_df_resolve, |
---|
1860 | 3268 | .check_member = btf_enum_check_member, |
---|
| 3269 | + .check_kflag_member = btf_enum_check_kflag_member, |
---|
1861 | 3270 | .log_details = btf_enum_log, |
---|
1862 | | - .seq_show = btf_enum_seq_show, |
---|
| 3271 | + .show = btf_enum_show, |
---|
1863 | 3272 | }; |
---|
| 3273 | + |
---|
| 3274 | +static s32 btf_func_proto_check_meta(struct btf_verifier_env *env, |
---|
| 3275 | + const struct btf_type *t, |
---|
| 3276 | + u32 meta_left) |
---|
| 3277 | +{ |
---|
| 3278 | + u32 meta_needed = btf_type_vlen(t) * sizeof(struct btf_param); |
---|
| 3279 | + |
---|
| 3280 | + if (meta_left < meta_needed) { |
---|
| 3281 | + btf_verifier_log_basic(env, t, |
---|
| 3282 | + "meta_left:%u meta_needed:%u", |
---|
| 3283 | + meta_left, meta_needed); |
---|
| 3284 | + return -EINVAL; |
---|
| 3285 | + } |
---|
| 3286 | + |
---|
| 3287 | + if (t->name_off) { |
---|
| 3288 | + btf_verifier_log_type(env, t, "Invalid name"); |
---|
| 3289 | + return -EINVAL; |
---|
| 3290 | + } |
---|
| 3291 | + |
---|
| 3292 | + if (btf_type_kflag(t)) { |
---|
| 3293 | + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); |
---|
| 3294 | + return -EINVAL; |
---|
| 3295 | + } |
---|
| 3296 | + |
---|
| 3297 | + btf_verifier_log_type(env, t, NULL); |
---|
| 3298 | + |
---|
| 3299 | + return meta_needed; |
---|
| 3300 | +} |
---|
| 3301 | + |
---|
| 3302 | +static void btf_func_proto_log(struct btf_verifier_env *env, |
---|
| 3303 | + const struct btf_type *t) |
---|
| 3304 | +{ |
---|
| 3305 | + const struct btf_param *args = (const struct btf_param *)(t + 1); |
---|
| 3306 | + u16 nr_args = btf_type_vlen(t), i; |
---|
| 3307 | + |
---|
| 3308 | + btf_verifier_log(env, "return=%u args=(", t->type); |
---|
| 3309 | + if (!nr_args) { |
---|
| 3310 | + btf_verifier_log(env, "void"); |
---|
| 3311 | + goto done; |
---|
| 3312 | + } |
---|
| 3313 | + |
---|
| 3314 | + if (nr_args == 1 && !args[0].type) { |
---|
| 3315 | + /* Only one vararg */ |
---|
| 3316 | + btf_verifier_log(env, "vararg"); |
---|
| 3317 | + goto done; |
---|
| 3318 | + } |
---|
| 3319 | + |
---|
| 3320 | + btf_verifier_log(env, "%u %s", args[0].type, |
---|
| 3321 | + __btf_name_by_offset(env->btf, |
---|
| 3322 | + args[0].name_off)); |
---|
| 3323 | + for (i = 1; i < nr_args - 1; i++) |
---|
| 3324 | + btf_verifier_log(env, ", %u %s", args[i].type, |
---|
| 3325 | + __btf_name_by_offset(env->btf, |
---|
| 3326 | + args[i].name_off)); |
---|
| 3327 | + |
---|
| 3328 | + if (nr_args > 1) { |
---|
| 3329 | + const struct btf_param *last_arg = &args[nr_args - 1]; |
---|
| 3330 | + |
---|
| 3331 | + if (last_arg->type) |
---|
| 3332 | + btf_verifier_log(env, ", %u %s", last_arg->type, |
---|
| 3333 | + __btf_name_by_offset(env->btf, |
---|
| 3334 | + last_arg->name_off)); |
---|
| 3335 | + else |
---|
| 3336 | + btf_verifier_log(env, ", vararg"); |
---|
| 3337 | + } |
---|
| 3338 | + |
---|
| 3339 | +done: |
---|
| 3340 | + btf_verifier_log(env, ")"); |
---|
| 3341 | +} |
---|
| 3342 | + |
---|
| 3343 | +static struct btf_kind_operations func_proto_ops = { |
---|
| 3344 | + .check_meta = btf_func_proto_check_meta, |
---|
| 3345 | + .resolve = btf_df_resolve, |
---|
| 3346 | + /* |
---|
| 3347 | + * BTF_KIND_FUNC_PROTO cannot be directly referred by |
---|
| 3348 | + * a struct's member. |
---|
| 3349 | + * |
---|
| 3350 | + * It should be a funciton pointer instead. |
---|
| 3351 | + * (i.e. struct's member -> BTF_KIND_PTR -> BTF_KIND_FUNC_PROTO) |
---|
| 3352 | + * |
---|
| 3353 | + * Hence, there is no btf_func_check_member(). |
---|
| 3354 | + */ |
---|
| 3355 | + .check_member = btf_df_check_member, |
---|
| 3356 | + .check_kflag_member = btf_df_check_kflag_member, |
---|
| 3357 | + .log_details = btf_func_proto_log, |
---|
| 3358 | + .show = btf_df_show, |
---|
| 3359 | +}; |
---|
| 3360 | + |
---|
| 3361 | +static s32 btf_func_check_meta(struct btf_verifier_env *env, |
---|
| 3362 | + const struct btf_type *t, |
---|
| 3363 | + u32 meta_left) |
---|
| 3364 | +{ |
---|
| 3365 | + if (!t->name_off || |
---|
| 3366 | + !btf_name_valid_identifier(env->btf, t->name_off)) { |
---|
| 3367 | + btf_verifier_log_type(env, t, "Invalid name"); |
---|
| 3368 | + return -EINVAL; |
---|
| 3369 | + } |
---|
| 3370 | + |
---|
| 3371 | + if (btf_type_vlen(t) > BTF_FUNC_GLOBAL) { |
---|
| 3372 | + btf_verifier_log_type(env, t, "Invalid func linkage"); |
---|
| 3373 | + return -EINVAL; |
---|
| 3374 | + } |
---|
| 3375 | + |
---|
| 3376 | + if (btf_type_kflag(t)) { |
---|
| 3377 | + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); |
---|
| 3378 | + return -EINVAL; |
---|
| 3379 | + } |
---|
| 3380 | + |
---|
| 3381 | + btf_verifier_log_type(env, t, NULL); |
---|
| 3382 | + |
---|
| 3383 | + return 0; |
---|
| 3384 | +} |
---|
| 3385 | + |
---|
| 3386 | +static struct btf_kind_operations func_ops = { |
---|
| 3387 | + .check_meta = btf_func_check_meta, |
---|
| 3388 | + .resolve = btf_df_resolve, |
---|
| 3389 | + .check_member = btf_df_check_member, |
---|
| 3390 | + .check_kflag_member = btf_df_check_kflag_member, |
---|
| 3391 | + .log_details = btf_ref_type_log, |
---|
| 3392 | + .show = btf_df_show, |
---|
| 3393 | +}; |
---|
| 3394 | + |
---|
| 3395 | +static s32 btf_var_check_meta(struct btf_verifier_env *env, |
---|
| 3396 | + const struct btf_type *t, |
---|
| 3397 | + u32 meta_left) |
---|
| 3398 | +{ |
---|
| 3399 | + const struct btf_var *var; |
---|
| 3400 | + u32 meta_needed = sizeof(*var); |
---|
| 3401 | + |
---|
| 3402 | + if (meta_left < meta_needed) { |
---|
| 3403 | + btf_verifier_log_basic(env, t, |
---|
| 3404 | + "meta_left:%u meta_needed:%u", |
---|
| 3405 | + meta_left, meta_needed); |
---|
| 3406 | + return -EINVAL; |
---|
| 3407 | + } |
---|
| 3408 | + |
---|
| 3409 | + if (btf_type_vlen(t)) { |
---|
| 3410 | + btf_verifier_log_type(env, t, "vlen != 0"); |
---|
| 3411 | + return -EINVAL; |
---|
| 3412 | + } |
---|
| 3413 | + |
---|
| 3414 | + if (btf_type_kflag(t)) { |
---|
| 3415 | + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); |
---|
| 3416 | + return -EINVAL; |
---|
| 3417 | + } |
---|
| 3418 | + |
---|
| 3419 | + if (!t->name_off || |
---|
| 3420 | + !__btf_name_valid(env->btf, t->name_off, true)) { |
---|
| 3421 | + btf_verifier_log_type(env, t, "Invalid name"); |
---|
| 3422 | + return -EINVAL; |
---|
| 3423 | + } |
---|
| 3424 | + |
---|
| 3425 | + /* A var cannot be in type void */ |
---|
| 3426 | + if (!t->type || !BTF_TYPE_ID_VALID(t->type)) { |
---|
| 3427 | + btf_verifier_log_type(env, t, "Invalid type_id"); |
---|
| 3428 | + return -EINVAL; |
---|
| 3429 | + } |
---|
| 3430 | + |
---|
| 3431 | + var = btf_type_var(t); |
---|
| 3432 | + if (var->linkage != BTF_VAR_STATIC && |
---|
| 3433 | + var->linkage != BTF_VAR_GLOBAL_ALLOCATED) { |
---|
| 3434 | + btf_verifier_log_type(env, t, "Linkage not supported"); |
---|
| 3435 | + return -EINVAL; |
---|
| 3436 | + } |
---|
| 3437 | + |
---|
| 3438 | + btf_verifier_log_type(env, t, NULL); |
---|
| 3439 | + |
---|
| 3440 | + return meta_needed; |
---|
| 3441 | +} |
---|
| 3442 | + |
---|
| 3443 | +static void btf_var_log(struct btf_verifier_env *env, const struct btf_type *t) |
---|
| 3444 | +{ |
---|
| 3445 | + const struct btf_var *var = btf_type_var(t); |
---|
| 3446 | + |
---|
| 3447 | + btf_verifier_log(env, "type_id=%u linkage=%u", t->type, var->linkage); |
---|
| 3448 | +} |
---|
| 3449 | + |
---|
| 3450 | +static const struct btf_kind_operations var_ops = { |
---|
| 3451 | + .check_meta = btf_var_check_meta, |
---|
| 3452 | + .resolve = btf_var_resolve, |
---|
| 3453 | + .check_member = btf_df_check_member, |
---|
| 3454 | + .check_kflag_member = btf_df_check_kflag_member, |
---|
| 3455 | + .log_details = btf_var_log, |
---|
| 3456 | + .show = btf_var_show, |
---|
| 3457 | +}; |
---|
| 3458 | + |
---|
| 3459 | +static s32 btf_datasec_check_meta(struct btf_verifier_env *env, |
---|
| 3460 | + const struct btf_type *t, |
---|
| 3461 | + u32 meta_left) |
---|
| 3462 | +{ |
---|
| 3463 | + const struct btf_var_secinfo *vsi; |
---|
| 3464 | + u64 last_vsi_end_off = 0, sum = 0; |
---|
| 3465 | + u32 i, meta_needed; |
---|
| 3466 | + |
---|
| 3467 | + meta_needed = btf_type_vlen(t) * sizeof(*vsi); |
---|
| 3468 | + if (meta_left < meta_needed) { |
---|
| 3469 | + btf_verifier_log_basic(env, t, |
---|
| 3470 | + "meta_left:%u meta_needed:%u", |
---|
| 3471 | + meta_left, meta_needed); |
---|
| 3472 | + return -EINVAL; |
---|
| 3473 | + } |
---|
| 3474 | + |
---|
| 3475 | + if (!btf_type_vlen(t)) { |
---|
| 3476 | + btf_verifier_log_type(env, t, "vlen == 0"); |
---|
| 3477 | + return -EINVAL; |
---|
| 3478 | + } |
---|
| 3479 | + |
---|
| 3480 | + if (!t->size) { |
---|
| 3481 | + btf_verifier_log_type(env, t, "size == 0"); |
---|
| 3482 | + return -EINVAL; |
---|
| 3483 | + } |
---|
| 3484 | + |
---|
| 3485 | + if (btf_type_kflag(t)) { |
---|
| 3486 | + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); |
---|
| 3487 | + return -EINVAL; |
---|
| 3488 | + } |
---|
| 3489 | + |
---|
| 3490 | + if (!t->name_off || |
---|
| 3491 | + !btf_name_valid_section(env->btf, t->name_off)) { |
---|
| 3492 | + btf_verifier_log_type(env, t, "Invalid name"); |
---|
| 3493 | + return -EINVAL; |
---|
| 3494 | + } |
---|
| 3495 | + |
---|
| 3496 | + btf_verifier_log_type(env, t, NULL); |
---|
| 3497 | + |
---|
| 3498 | + for_each_vsi(i, t, vsi) { |
---|
| 3499 | + /* A var cannot be in type void */ |
---|
| 3500 | + if (!vsi->type || !BTF_TYPE_ID_VALID(vsi->type)) { |
---|
| 3501 | + btf_verifier_log_vsi(env, t, vsi, |
---|
| 3502 | + "Invalid type_id"); |
---|
| 3503 | + return -EINVAL; |
---|
| 3504 | + } |
---|
| 3505 | + |
---|
| 3506 | + if (vsi->offset < last_vsi_end_off || vsi->offset >= t->size) { |
---|
| 3507 | + btf_verifier_log_vsi(env, t, vsi, |
---|
| 3508 | + "Invalid offset"); |
---|
| 3509 | + return -EINVAL; |
---|
| 3510 | + } |
---|
| 3511 | + |
---|
| 3512 | + if (!vsi->size || vsi->size > t->size) { |
---|
| 3513 | + btf_verifier_log_vsi(env, t, vsi, |
---|
| 3514 | + "Invalid size"); |
---|
| 3515 | + return -EINVAL; |
---|
| 3516 | + } |
---|
| 3517 | + |
---|
| 3518 | + last_vsi_end_off = vsi->offset + vsi->size; |
---|
| 3519 | + if (last_vsi_end_off > t->size) { |
---|
| 3520 | + btf_verifier_log_vsi(env, t, vsi, |
---|
| 3521 | + "Invalid offset+size"); |
---|
| 3522 | + return -EINVAL; |
---|
| 3523 | + } |
---|
| 3524 | + |
---|
| 3525 | + btf_verifier_log_vsi(env, t, vsi, NULL); |
---|
| 3526 | + sum += vsi->size; |
---|
| 3527 | + } |
---|
| 3528 | + |
---|
| 3529 | + if (t->size < sum) { |
---|
| 3530 | + btf_verifier_log_type(env, t, "Invalid btf_info size"); |
---|
| 3531 | + return -EINVAL; |
---|
| 3532 | + } |
---|
| 3533 | + |
---|
| 3534 | + return meta_needed; |
---|
| 3535 | +} |
---|
| 3536 | + |
---|
| 3537 | +static int btf_datasec_resolve(struct btf_verifier_env *env, |
---|
| 3538 | + const struct resolve_vertex *v) |
---|
| 3539 | +{ |
---|
| 3540 | + const struct btf_var_secinfo *vsi; |
---|
| 3541 | + struct btf *btf = env->btf; |
---|
| 3542 | + u16 i; |
---|
| 3543 | + |
---|
| 3544 | + for_each_vsi_from(i, v->next_member, v->t, vsi) { |
---|
| 3545 | + u32 var_type_id = vsi->type, type_id, type_size = 0; |
---|
| 3546 | + const struct btf_type *var_type = btf_type_by_id(env->btf, |
---|
| 3547 | + var_type_id); |
---|
| 3548 | + if (!var_type || !btf_type_is_var(var_type)) { |
---|
| 3549 | + btf_verifier_log_vsi(env, v->t, vsi, |
---|
| 3550 | + "Not a VAR kind member"); |
---|
| 3551 | + return -EINVAL; |
---|
| 3552 | + } |
---|
| 3553 | + |
---|
| 3554 | + if (!env_type_is_resolve_sink(env, var_type) && |
---|
| 3555 | + !env_type_is_resolved(env, var_type_id)) { |
---|
| 3556 | + env_stack_set_next_member(env, i + 1); |
---|
| 3557 | + return env_stack_push(env, var_type, var_type_id); |
---|
| 3558 | + } |
---|
| 3559 | + |
---|
| 3560 | + type_id = var_type->type; |
---|
| 3561 | + if (!btf_type_id_size(btf, &type_id, &type_size)) { |
---|
| 3562 | + btf_verifier_log_vsi(env, v->t, vsi, "Invalid type"); |
---|
| 3563 | + return -EINVAL; |
---|
| 3564 | + } |
---|
| 3565 | + |
---|
| 3566 | + if (vsi->size < type_size) { |
---|
| 3567 | + btf_verifier_log_vsi(env, v->t, vsi, "Invalid size"); |
---|
| 3568 | + return -EINVAL; |
---|
| 3569 | + } |
---|
| 3570 | + } |
---|
| 3571 | + |
---|
| 3572 | + env_stack_pop_resolved(env, 0, 0); |
---|
| 3573 | + return 0; |
---|
| 3574 | +} |
---|
| 3575 | + |
---|
| 3576 | +static void btf_datasec_log(struct btf_verifier_env *env, |
---|
| 3577 | + const struct btf_type *t) |
---|
| 3578 | +{ |
---|
| 3579 | + btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); |
---|
| 3580 | +} |
---|
| 3581 | + |
---|
| 3582 | +static void btf_datasec_show(const struct btf *btf, |
---|
| 3583 | + const struct btf_type *t, u32 type_id, |
---|
| 3584 | + void *data, u8 bits_offset, |
---|
| 3585 | + struct btf_show *show) |
---|
| 3586 | +{ |
---|
| 3587 | + const struct btf_var_secinfo *vsi; |
---|
| 3588 | + const struct btf_type *var; |
---|
| 3589 | + u32 i; |
---|
| 3590 | + |
---|
| 3591 | + if (!btf_show_start_type(show, t, type_id, data)) |
---|
| 3592 | + return; |
---|
| 3593 | + |
---|
| 3594 | + btf_show_type_value(show, "section (\"%s\") = {", |
---|
| 3595 | + __btf_name_by_offset(btf, t->name_off)); |
---|
| 3596 | + for_each_vsi(i, t, vsi) { |
---|
| 3597 | + var = btf_type_by_id(btf, vsi->type); |
---|
| 3598 | + if (i) |
---|
| 3599 | + btf_show(show, ","); |
---|
| 3600 | + btf_type_ops(var)->show(btf, var, vsi->type, |
---|
| 3601 | + data + vsi->offset, bits_offset, show); |
---|
| 3602 | + } |
---|
| 3603 | + btf_show_end_type(show); |
---|
| 3604 | +} |
---|
| 3605 | + |
---|
| 3606 | +static const struct btf_kind_operations datasec_ops = { |
---|
| 3607 | + .check_meta = btf_datasec_check_meta, |
---|
| 3608 | + .resolve = btf_datasec_resolve, |
---|
| 3609 | + .check_member = btf_df_check_member, |
---|
| 3610 | + .check_kflag_member = btf_df_check_kflag_member, |
---|
| 3611 | + .log_details = btf_datasec_log, |
---|
| 3612 | + .show = btf_datasec_show, |
---|
| 3613 | +}; |
---|
| 3614 | + |
---|
| 3615 | +static int btf_func_proto_check(struct btf_verifier_env *env, |
---|
| 3616 | + const struct btf_type *t) |
---|
| 3617 | +{ |
---|
| 3618 | + const struct btf_type *ret_type; |
---|
| 3619 | + const struct btf_param *args; |
---|
| 3620 | + const struct btf *btf; |
---|
| 3621 | + u16 nr_args, i; |
---|
| 3622 | + int err; |
---|
| 3623 | + |
---|
| 3624 | + btf = env->btf; |
---|
| 3625 | + args = (const struct btf_param *)(t + 1); |
---|
| 3626 | + nr_args = btf_type_vlen(t); |
---|
| 3627 | + |
---|
| 3628 | + /* Check func return type which could be "void" (t->type == 0) */ |
---|
| 3629 | + if (t->type) { |
---|
| 3630 | + u32 ret_type_id = t->type; |
---|
| 3631 | + |
---|
| 3632 | + ret_type = btf_type_by_id(btf, ret_type_id); |
---|
| 3633 | + if (!ret_type) { |
---|
| 3634 | + btf_verifier_log_type(env, t, "Invalid return type"); |
---|
| 3635 | + return -EINVAL; |
---|
| 3636 | + } |
---|
| 3637 | + |
---|
| 3638 | + if (btf_type_needs_resolve(ret_type) && |
---|
| 3639 | + !env_type_is_resolved(env, ret_type_id)) { |
---|
| 3640 | + err = btf_resolve(env, ret_type, ret_type_id); |
---|
| 3641 | + if (err) |
---|
| 3642 | + return err; |
---|
| 3643 | + } |
---|
| 3644 | + |
---|
| 3645 | + /* Ensure the return type is a type that has a size */ |
---|
| 3646 | + if (!btf_type_id_size(btf, &ret_type_id, NULL)) { |
---|
| 3647 | + btf_verifier_log_type(env, t, "Invalid return type"); |
---|
| 3648 | + return -EINVAL; |
---|
| 3649 | + } |
---|
| 3650 | + } |
---|
| 3651 | + |
---|
| 3652 | + if (!nr_args) |
---|
| 3653 | + return 0; |
---|
| 3654 | + |
---|
| 3655 | + /* Last func arg type_id could be 0 if it is a vararg */ |
---|
| 3656 | + if (!args[nr_args - 1].type) { |
---|
| 3657 | + if (args[nr_args - 1].name_off) { |
---|
| 3658 | + btf_verifier_log_type(env, t, "Invalid arg#%u", |
---|
| 3659 | + nr_args); |
---|
| 3660 | + return -EINVAL; |
---|
| 3661 | + } |
---|
| 3662 | + nr_args--; |
---|
| 3663 | + } |
---|
| 3664 | + |
---|
| 3665 | + err = 0; |
---|
| 3666 | + for (i = 0; i < nr_args; i++) { |
---|
| 3667 | + const struct btf_type *arg_type; |
---|
| 3668 | + u32 arg_type_id; |
---|
| 3669 | + |
---|
| 3670 | + arg_type_id = args[i].type; |
---|
| 3671 | + arg_type = btf_type_by_id(btf, arg_type_id); |
---|
| 3672 | + if (!arg_type) { |
---|
| 3673 | + btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); |
---|
| 3674 | + err = -EINVAL; |
---|
| 3675 | + break; |
---|
| 3676 | + } |
---|
| 3677 | + |
---|
| 3678 | + if (args[i].name_off && |
---|
| 3679 | + (!btf_name_offset_valid(btf, args[i].name_off) || |
---|
| 3680 | + !btf_name_valid_identifier(btf, args[i].name_off))) { |
---|
| 3681 | + btf_verifier_log_type(env, t, |
---|
| 3682 | + "Invalid arg#%u", i + 1); |
---|
| 3683 | + err = -EINVAL; |
---|
| 3684 | + break; |
---|
| 3685 | + } |
---|
| 3686 | + |
---|
| 3687 | + if (btf_type_needs_resolve(arg_type) && |
---|
| 3688 | + !env_type_is_resolved(env, arg_type_id)) { |
---|
| 3689 | + err = btf_resolve(env, arg_type, arg_type_id); |
---|
| 3690 | + if (err) |
---|
| 3691 | + break; |
---|
| 3692 | + } |
---|
| 3693 | + |
---|
| 3694 | + if (!btf_type_id_size(btf, &arg_type_id, NULL)) { |
---|
| 3695 | + btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); |
---|
| 3696 | + err = -EINVAL; |
---|
| 3697 | + break; |
---|
| 3698 | + } |
---|
| 3699 | + } |
---|
| 3700 | + |
---|
| 3701 | + return err; |
---|
| 3702 | +} |
---|
| 3703 | + |
---|
| 3704 | +static int btf_func_check(struct btf_verifier_env *env, |
---|
| 3705 | + const struct btf_type *t) |
---|
| 3706 | +{ |
---|
| 3707 | + const struct btf_type *proto_type; |
---|
| 3708 | + const struct btf_param *args; |
---|
| 3709 | + const struct btf *btf; |
---|
| 3710 | + u16 nr_args, i; |
---|
| 3711 | + |
---|
| 3712 | + btf = env->btf; |
---|
| 3713 | + proto_type = btf_type_by_id(btf, t->type); |
---|
| 3714 | + |
---|
| 3715 | + if (!proto_type || !btf_type_is_func_proto(proto_type)) { |
---|
| 3716 | + btf_verifier_log_type(env, t, "Invalid type_id"); |
---|
| 3717 | + return -EINVAL; |
---|
| 3718 | + } |
---|
| 3719 | + |
---|
| 3720 | + args = (const struct btf_param *)(proto_type + 1); |
---|
| 3721 | + nr_args = btf_type_vlen(proto_type); |
---|
| 3722 | + for (i = 0; i < nr_args; i++) { |
---|
| 3723 | + if (!args[i].name_off && args[i].type) { |
---|
| 3724 | + btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); |
---|
| 3725 | + return -EINVAL; |
---|
| 3726 | + } |
---|
| 3727 | + } |
---|
| 3728 | + |
---|
| 3729 | + return 0; |
---|
| 3730 | +} |
---|
1864 | 3731 | |
---|
1865 | 3732 | static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = { |
---|
1866 | 3733 | [BTF_KIND_INT] = &int_ops, |
---|
.. | .. |
---|
1874 | 3741 | [BTF_KIND_VOLATILE] = &modifier_ops, |
---|
1875 | 3742 | [BTF_KIND_CONST] = &modifier_ops, |
---|
1876 | 3743 | [BTF_KIND_RESTRICT] = &modifier_ops, |
---|
| 3744 | + [BTF_KIND_FUNC] = &func_ops, |
---|
| 3745 | + [BTF_KIND_FUNC_PROTO] = &func_proto_ops, |
---|
| 3746 | + [BTF_KIND_VAR] = &var_ops, |
---|
| 3747 | + [BTF_KIND_DATASEC] = &datasec_ops, |
---|
1877 | 3748 | }; |
---|
1878 | 3749 | |
---|
1879 | 3750 | static s32 btf_check_meta(struct btf_verifier_env *env, |
---|
.. | .. |
---|
1945 | 3816 | return 0; |
---|
1946 | 3817 | } |
---|
1947 | 3818 | |
---|
1948 | | -static int btf_resolve(struct btf_verifier_env *env, |
---|
1949 | | - const struct btf_type *t, u32 type_id) |
---|
1950 | | -{ |
---|
1951 | | - const struct resolve_vertex *v; |
---|
1952 | | - int err = 0; |
---|
1953 | | - |
---|
1954 | | - env->resolve_mode = RESOLVE_TBD; |
---|
1955 | | - env_stack_push(env, t, type_id); |
---|
1956 | | - while (!err && (v = env_stack_peak(env))) { |
---|
1957 | | - env->log_type_id = v->type_id; |
---|
1958 | | - err = btf_type_ops(v->t)->resolve(env, v); |
---|
1959 | | - } |
---|
1960 | | - |
---|
1961 | | - env->log_type_id = type_id; |
---|
1962 | | - if (err == -E2BIG) |
---|
1963 | | - btf_verifier_log_type(env, t, |
---|
1964 | | - "Exceeded max resolving depth:%u", |
---|
1965 | | - MAX_RESOLVE_DEPTH); |
---|
1966 | | - else if (err == -EEXIST) |
---|
1967 | | - btf_verifier_log_type(env, t, "Loop detected"); |
---|
1968 | | - |
---|
1969 | | - return err; |
---|
1970 | | -} |
---|
1971 | | - |
---|
1972 | 3819 | static bool btf_resolve_valid(struct btf_verifier_env *env, |
---|
1973 | 3820 | const struct btf_type *t, |
---|
1974 | 3821 | u32 type_id) |
---|
.. | .. |
---|
1978 | 3825 | if (!env_type_is_resolved(env, type_id)) |
---|
1979 | 3826 | return false; |
---|
1980 | 3827 | |
---|
1981 | | - if (btf_type_is_struct(t)) |
---|
| 3828 | + if (btf_type_is_struct(t) || btf_type_is_datasec(t)) |
---|
1982 | 3829 | return !btf->resolved_ids[type_id] && |
---|
1983 | | - !btf->resolved_sizes[type_id]; |
---|
| 3830 | + !btf->resolved_sizes[type_id]; |
---|
1984 | 3831 | |
---|
1985 | | - if (btf_type_is_modifier(t) || btf_type_is_ptr(t)) { |
---|
| 3832 | + if (btf_type_is_modifier(t) || btf_type_is_ptr(t) || |
---|
| 3833 | + btf_type_is_var(t)) { |
---|
1986 | 3834 | t = btf_type_id_resolve(btf, &type_id); |
---|
1987 | | - return t && !btf_type_is_modifier(t); |
---|
| 3835 | + return t && |
---|
| 3836 | + !btf_type_is_modifier(t) && |
---|
| 3837 | + !btf_type_is_var(t) && |
---|
| 3838 | + !btf_type_is_datasec(t); |
---|
1988 | 3839 | } |
---|
1989 | 3840 | |
---|
1990 | 3841 | if (btf_type_is_array(t)) { |
---|
.. | .. |
---|
2000 | 3851 | } |
---|
2001 | 3852 | |
---|
2002 | 3853 | return false; |
---|
| 3854 | +} |
---|
| 3855 | + |
---|
| 3856 | +static int btf_resolve(struct btf_verifier_env *env, |
---|
| 3857 | + const struct btf_type *t, u32 type_id) |
---|
| 3858 | +{ |
---|
| 3859 | + u32 save_log_type_id = env->log_type_id; |
---|
| 3860 | + const struct resolve_vertex *v; |
---|
| 3861 | + int err = 0; |
---|
| 3862 | + |
---|
| 3863 | + env->resolve_mode = RESOLVE_TBD; |
---|
| 3864 | + env_stack_push(env, t, type_id); |
---|
| 3865 | + while (!err && (v = env_stack_peak(env))) { |
---|
| 3866 | + env->log_type_id = v->type_id; |
---|
| 3867 | + err = btf_type_ops(v->t)->resolve(env, v); |
---|
| 3868 | + } |
---|
| 3869 | + |
---|
| 3870 | + env->log_type_id = type_id; |
---|
| 3871 | + if (err == -E2BIG) { |
---|
| 3872 | + btf_verifier_log_type(env, t, |
---|
| 3873 | + "Exceeded max resolving depth:%u", |
---|
| 3874 | + MAX_RESOLVE_DEPTH); |
---|
| 3875 | + } else if (err == -EEXIST) { |
---|
| 3876 | + btf_verifier_log_type(env, t, "Loop detected"); |
---|
| 3877 | + } |
---|
| 3878 | + |
---|
| 3879 | + /* Final sanity check */ |
---|
| 3880 | + if (!err && !btf_resolve_valid(env, t, type_id)) { |
---|
| 3881 | + btf_verifier_log_type(env, t, "Invalid resolve state"); |
---|
| 3882 | + err = -EINVAL; |
---|
| 3883 | + } |
---|
| 3884 | + |
---|
| 3885 | + env->log_type_id = save_log_type_id; |
---|
| 3886 | + return err; |
---|
2003 | 3887 | } |
---|
2004 | 3888 | |
---|
2005 | 3889 | static int btf_check_all_types(struct btf_verifier_env *env) |
---|
.. | .. |
---|
2024 | 3908 | return err; |
---|
2025 | 3909 | } |
---|
2026 | 3910 | |
---|
2027 | | - if (btf_type_needs_resolve(t) && |
---|
2028 | | - !btf_resolve_valid(env, t, type_id)) { |
---|
2029 | | - btf_verifier_log_type(env, t, "Invalid resolve state"); |
---|
2030 | | - return -EINVAL; |
---|
| 3911 | + if (btf_type_is_func_proto(t)) { |
---|
| 3912 | + err = btf_func_proto_check(env, t); |
---|
| 3913 | + if (err) |
---|
| 3914 | + return err; |
---|
| 3915 | + } |
---|
| 3916 | + |
---|
| 3917 | + if (btf_type_is_func(t)) { |
---|
| 3918 | + err = btf_func_check(env, t); |
---|
| 3919 | + if (err) |
---|
| 3920 | + return err; |
---|
2031 | 3921 | } |
---|
2032 | 3922 | } |
---|
2033 | 3923 | |
---|
.. | .. |
---|
2190 | 4080 | |
---|
2191 | 4081 | hdr = &btf->hdr; |
---|
2192 | 4082 | |
---|
2193 | | - if (hdr->hdr_len != hdr_len) |
---|
2194 | | - return -EINVAL; |
---|
2195 | | - |
---|
2196 | 4083 | btf_verifier_log_hdr(env, btf_data_size); |
---|
2197 | 4084 | |
---|
2198 | 4085 | if (hdr->magic != BTF_MAGIC) { |
---|
.. | .. |
---|
2248 | 4135 | log->len_total = log_size; |
---|
2249 | 4136 | |
---|
2250 | 4137 | /* log attributes have to be sane */ |
---|
2251 | | - if (log->len_total < 128 || log->len_total > UINT_MAX >> 8 || |
---|
2252 | | - !log->level || !log->ubuf) { |
---|
| 4138 | + if (!bpf_verifier_log_attr_valid(log)) { |
---|
2253 | 4139 | err = -EINVAL; |
---|
2254 | 4140 | goto errout; |
---|
2255 | 4141 | } |
---|
.. | .. |
---|
2306 | 4192 | return ERR_PTR(err); |
---|
2307 | 4193 | } |
---|
2308 | 4194 | |
---|
2309 | | -void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj, |
---|
2310 | | - struct seq_file *m) |
---|
| 4195 | +extern char __weak __start_BTF[]; |
---|
| 4196 | +extern char __weak __stop_BTF[]; |
---|
| 4197 | +extern struct btf *btf_vmlinux; |
---|
| 4198 | + |
---|
| 4199 | +#define BPF_MAP_TYPE(_id, _ops) |
---|
| 4200 | +#define BPF_LINK_TYPE(_id, _name) |
---|
| 4201 | +static union { |
---|
| 4202 | + struct bpf_ctx_convert { |
---|
| 4203 | +#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ |
---|
| 4204 | + prog_ctx_type _id##_prog; \ |
---|
| 4205 | + kern_ctx_type _id##_kern; |
---|
| 4206 | +#include <linux/bpf_types.h> |
---|
| 4207 | +#undef BPF_PROG_TYPE |
---|
| 4208 | + } *__t; |
---|
| 4209 | + /* 't' is written once under lock. Read many times. */ |
---|
| 4210 | + const struct btf_type *t; |
---|
| 4211 | +} bpf_ctx_convert; |
---|
| 4212 | +enum { |
---|
| 4213 | +#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ |
---|
| 4214 | + __ctx_convert##_id, |
---|
| 4215 | +#include <linux/bpf_types.h> |
---|
| 4216 | +#undef BPF_PROG_TYPE |
---|
| 4217 | + __ctx_convert_unused, /* to avoid empty enum in extreme .config */ |
---|
| 4218 | +}; |
---|
| 4219 | +static u8 bpf_ctx_convert_map[] = { |
---|
| 4220 | +#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ |
---|
| 4221 | + [_id] = __ctx_convert##_id, |
---|
| 4222 | +#include <linux/bpf_types.h> |
---|
| 4223 | +#undef BPF_PROG_TYPE |
---|
| 4224 | + 0, /* avoid empty array */ |
---|
| 4225 | +}; |
---|
| 4226 | +#undef BPF_MAP_TYPE |
---|
| 4227 | +#undef BPF_LINK_TYPE |
---|
| 4228 | + |
---|
| 4229 | +static const struct btf_member * |
---|
| 4230 | +btf_get_prog_ctx_type(struct bpf_verifier_log *log, struct btf *btf, |
---|
| 4231 | + const struct btf_type *t, enum bpf_prog_type prog_type, |
---|
| 4232 | + int arg) |
---|
| 4233 | +{ |
---|
| 4234 | + const struct btf_type *conv_struct; |
---|
| 4235 | + const struct btf_type *ctx_struct; |
---|
| 4236 | + const struct btf_member *ctx_type; |
---|
| 4237 | + const char *tname, *ctx_tname; |
---|
| 4238 | + |
---|
| 4239 | + conv_struct = bpf_ctx_convert.t; |
---|
| 4240 | + if (!conv_struct) { |
---|
| 4241 | + bpf_log(log, "btf_vmlinux is malformed\n"); |
---|
| 4242 | + return NULL; |
---|
| 4243 | + } |
---|
| 4244 | + t = btf_type_by_id(btf, t->type); |
---|
| 4245 | + while (btf_type_is_modifier(t)) |
---|
| 4246 | + t = btf_type_by_id(btf, t->type); |
---|
| 4247 | + if (!btf_type_is_struct(t)) { |
---|
| 4248 | + /* Only pointer to struct is supported for now. |
---|
| 4249 | + * That means that BPF_PROG_TYPE_TRACEPOINT with BTF |
---|
| 4250 | + * is not supported yet. |
---|
| 4251 | + * BPF_PROG_TYPE_RAW_TRACEPOINT is fine. |
---|
| 4252 | + */ |
---|
| 4253 | + if (log->level & BPF_LOG_LEVEL) |
---|
| 4254 | + bpf_log(log, "arg#%d type is not a struct\n", arg); |
---|
| 4255 | + return NULL; |
---|
| 4256 | + } |
---|
| 4257 | + tname = btf_name_by_offset(btf, t->name_off); |
---|
| 4258 | + if (!tname) { |
---|
| 4259 | + bpf_log(log, "arg#%d struct doesn't have a name\n", arg); |
---|
| 4260 | + return NULL; |
---|
| 4261 | + } |
---|
| 4262 | + /* prog_type is valid bpf program type. No need for bounds check. */ |
---|
| 4263 | + ctx_type = btf_type_member(conv_struct) + bpf_ctx_convert_map[prog_type] * 2; |
---|
| 4264 | + /* ctx_struct is a pointer to prog_ctx_type in vmlinux. |
---|
| 4265 | + * Like 'struct __sk_buff' |
---|
| 4266 | + */ |
---|
| 4267 | + ctx_struct = btf_type_by_id(btf_vmlinux, ctx_type->type); |
---|
| 4268 | + if (!ctx_struct) |
---|
| 4269 | + /* should not happen */ |
---|
| 4270 | + return NULL; |
---|
| 4271 | + ctx_tname = btf_name_by_offset(btf_vmlinux, ctx_struct->name_off); |
---|
| 4272 | + if (!ctx_tname) { |
---|
| 4273 | + /* should not happen */ |
---|
| 4274 | + bpf_log(log, "Please fix kernel include/linux/bpf_types.h\n"); |
---|
| 4275 | + return NULL; |
---|
| 4276 | + } |
---|
| 4277 | + /* only compare that prog's ctx type name is the same as |
---|
| 4278 | + * kernel expects. No need to compare field by field. |
---|
| 4279 | + * It's ok for bpf prog to do: |
---|
| 4280 | + * struct __sk_buff {}; |
---|
| 4281 | + * int socket_filter_bpf_prog(struct __sk_buff *skb) |
---|
| 4282 | + * { // no fields of skb are ever used } |
---|
| 4283 | + */ |
---|
| 4284 | + if (strcmp(ctx_tname, tname)) |
---|
| 4285 | + return NULL; |
---|
| 4286 | + return ctx_type; |
---|
| 4287 | +} |
---|
| 4288 | + |
---|
| 4289 | +static const struct bpf_map_ops * const btf_vmlinux_map_ops[] = { |
---|
| 4290 | +#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) |
---|
| 4291 | +#define BPF_LINK_TYPE(_id, _name) |
---|
| 4292 | +#define BPF_MAP_TYPE(_id, _ops) \ |
---|
| 4293 | + [_id] = &_ops, |
---|
| 4294 | +#include <linux/bpf_types.h> |
---|
| 4295 | +#undef BPF_PROG_TYPE |
---|
| 4296 | +#undef BPF_LINK_TYPE |
---|
| 4297 | +#undef BPF_MAP_TYPE |
---|
| 4298 | +}; |
---|
| 4299 | + |
---|
| 4300 | +static int btf_vmlinux_map_ids_init(const struct btf *btf, |
---|
| 4301 | + struct bpf_verifier_log *log) |
---|
| 4302 | +{ |
---|
| 4303 | + const struct bpf_map_ops *ops; |
---|
| 4304 | + int i, btf_id; |
---|
| 4305 | + |
---|
| 4306 | + for (i = 0; i < ARRAY_SIZE(btf_vmlinux_map_ops); ++i) { |
---|
| 4307 | + ops = btf_vmlinux_map_ops[i]; |
---|
| 4308 | + if (!ops || (!ops->map_btf_name && !ops->map_btf_id)) |
---|
| 4309 | + continue; |
---|
| 4310 | + if (!ops->map_btf_name || !ops->map_btf_id) { |
---|
| 4311 | + bpf_log(log, "map type %d is misconfigured\n", i); |
---|
| 4312 | + return -EINVAL; |
---|
| 4313 | + } |
---|
| 4314 | + btf_id = btf_find_by_name_kind(btf, ops->map_btf_name, |
---|
| 4315 | + BTF_KIND_STRUCT); |
---|
| 4316 | + if (btf_id < 0) |
---|
| 4317 | + return btf_id; |
---|
| 4318 | + *ops->map_btf_id = btf_id; |
---|
| 4319 | + } |
---|
| 4320 | + |
---|
| 4321 | + return 0; |
---|
| 4322 | +} |
---|
| 4323 | + |
---|
| 4324 | +static int btf_translate_to_vmlinux(struct bpf_verifier_log *log, |
---|
| 4325 | + struct btf *btf, |
---|
| 4326 | + const struct btf_type *t, |
---|
| 4327 | + enum bpf_prog_type prog_type, |
---|
| 4328 | + int arg) |
---|
| 4329 | +{ |
---|
| 4330 | + const struct btf_member *prog_ctx_type, *kern_ctx_type; |
---|
| 4331 | + |
---|
| 4332 | + prog_ctx_type = btf_get_prog_ctx_type(log, btf, t, prog_type, arg); |
---|
| 4333 | + if (!prog_ctx_type) |
---|
| 4334 | + return -ENOENT; |
---|
| 4335 | + kern_ctx_type = prog_ctx_type + 1; |
---|
| 4336 | + return kern_ctx_type->type; |
---|
| 4337 | +} |
---|
| 4338 | + |
---|
| 4339 | +BTF_ID_LIST(bpf_ctx_convert_btf_id) |
---|
| 4340 | +BTF_ID(struct, bpf_ctx_convert) |
---|
| 4341 | + |
---|
| 4342 | +struct btf *btf_parse_vmlinux(void) |
---|
| 4343 | +{ |
---|
| 4344 | + struct btf_verifier_env *env = NULL; |
---|
| 4345 | + struct bpf_verifier_log *log; |
---|
| 4346 | + struct btf *btf = NULL; |
---|
| 4347 | + int err; |
---|
| 4348 | + |
---|
| 4349 | + env = kzalloc(sizeof(*env), GFP_KERNEL | __GFP_NOWARN); |
---|
| 4350 | + if (!env) |
---|
| 4351 | + return ERR_PTR(-ENOMEM); |
---|
| 4352 | + |
---|
| 4353 | + log = &env->log; |
---|
| 4354 | + log->level = BPF_LOG_KERNEL; |
---|
| 4355 | + |
---|
| 4356 | + btf = kzalloc(sizeof(*btf), GFP_KERNEL | __GFP_NOWARN); |
---|
| 4357 | + if (!btf) { |
---|
| 4358 | + err = -ENOMEM; |
---|
| 4359 | + goto errout; |
---|
| 4360 | + } |
---|
| 4361 | + env->btf = btf; |
---|
| 4362 | + |
---|
| 4363 | + btf->data = __start_BTF; |
---|
| 4364 | + btf->data_size = __stop_BTF - __start_BTF; |
---|
| 4365 | + |
---|
| 4366 | + err = btf_parse_hdr(env); |
---|
| 4367 | + if (err) |
---|
| 4368 | + goto errout; |
---|
| 4369 | + |
---|
| 4370 | + btf->nohdr_data = btf->data + btf->hdr.hdr_len; |
---|
| 4371 | + |
---|
| 4372 | + err = btf_parse_str_sec(env); |
---|
| 4373 | + if (err) |
---|
| 4374 | + goto errout; |
---|
| 4375 | + |
---|
| 4376 | + err = btf_check_all_metas(env); |
---|
| 4377 | + if (err) |
---|
| 4378 | + goto errout; |
---|
| 4379 | + |
---|
| 4380 | + /* btf_parse_vmlinux() runs under bpf_verifier_lock */ |
---|
| 4381 | + bpf_ctx_convert.t = btf_type_by_id(btf, bpf_ctx_convert_btf_id[0]); |
---|
| 4382 | + |
---|
| 4383 | + /* find bpf map structs for map_ptr access checking */ |
---|
| 4384 | + err = btf_vmlinux_map_ids_init(btf, log); |
---|
| 4385 | + if (err < 0) |
---|
| 4386 | + goto errout; |
---|
| 4387 | + |
---|
| 4388 | + bpf_struct_ops_init(btf, log); |
---|
| 4389 | + |
---|
| 4390 | + btf_verifier_env_free(env); |
---|
| 4391 | + refcount_set(&btf->refcnt, 1); |
---|
| 4392 | + return btf; |
---|
| 4393 | + |
---|
| 4394 | +errout: |
---|
| 4395 | + btf_verifier_env_free(env); |
---|
| 4396 | + if (btf) { |
---|
| 4397 | + kvfree(btf->types); |
---|
| 4398 | + kfree(btf); |
---|
| 4399 | + } |
---|
| 4400 | + return ERR_PTR(err); |
---|
| 4401 | +} |
---|
| 4402 | + |
---|
| 4403 | +struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog) |
---|
| 4404 | +{ |
---|
| 4405 | + struct bpf_prog *tgt_prog = prog->aux->dst_prog; |
---|
| 4406 | + |
---|
| 4407 | + if (tgt_prog) { |
---|
| 4408 | + return tgt_prog->aux->btf; |
---|
| 4409 | + } else { |
---|
| 4410 | + return btf_vmlinux; |
---|
| 4411 | + } |
---|
| 4412 | +} |
---|
| 4413 | + |
---|
| 4414 | +static bool is_string_ptr(struct btf *btf, const struct btf_type *t) |
---|
| 4415 | +{ |
---|
| 4416 | + /* t comes in already as a pointer */ |
---|
| 4417 | + t = btf_type_by_id(btf, t->type); |
---|
| 4418 | + |
---|
| 4419 | + /* allow const */ |
---|
| 4420 | + if (BTF_INFO_KIND(t->info) == BTF_KIND_CONST) |
---|
| 4421 | + t = btf_type_by_id(btf, t->type); |
---|
| 4422 | + |
---|
| 4423 | + /* char, signed char, unsigned char */ |
---|
| 4424 | + return btf_type_is_int(t) && t->size == 1; |
---|
| 4425 | +} |
---|
| 4426 | + |
---|
| 4427 | +bool btf_ctx_access(int off, int size, enum bpf_access_type type, |
---|
| 4428 | + const struct bpf_prog *prog, |
---|
| 4429 | + struct bpf_insn_access_aux *info) |
---|
| 4430 | +{ |
---|
| 4431 | + const struct btf_type *t = prog->aux->attach_func_proto; |
---|
| 4432 | + struct bpf_prog *tgt_prog = prog->aux->dst_prog; |
---|
| 4433 | + struct btf *btf = bpf_prog_get_target_btf(prog); |
---|
| 4434 | + const char *tname = prog->aux->attach_func_name; |
---|
| 4435 | + struct bpf_verifier_log *log = info->log; |
---|
| 4436 | + const struct btf_param *args; |
---|
| 4437 | + u32 nr_args, arg; |
---|
| 4438 | + int i, ret; |
---|
| 4439 | + |
---|
| 4440 | + if (off % 8) { |
---|
| 4441 | + bpf_log(log, "func '%s' offset %d is not multiple of 8\n", |
---|
| 4442 | + tname, off); |
---|
| 4443 | + return false; |
---|
| 4444 | + } |
---|
| 4445 | + arg = off / 8; |
---|
| 4446 | + args = (const struct btf_param *)(t + 1); |
---|
| 4447 | + /* if (t == NULL) Fall back to default BPF prog with 5 u64 arguments */ |
---|
| 4448 | + nr_args = t ? btf_type_vlen(t) : 5; |
---|
| 4449 | + if (prog->aux->attach_btf_trace) { |
---|
| 4450 | + /* skip first 'void *__data' argument in btf_trace_##name typedef */ |
---|
| 4451 | + args++; |
---|
| 4452 | + nr_args--; |
---|
| 4453 | + } |
---|
| 4454 | + |
---|
| 4455 | + if (arg > nr_args) { |
---|
| 4456 | + bpf_log(log, "func '%s' doesn't have %d-th argument\n", |
---|
| 4457 | + tname, arg + 1); |
---|
| 4458 | + return false; |
---|
| 4459 | + } |
---|
| 4460 | + |
---|
| 4461 | + if (arg == nr_args) { |
---|
| 4462 | + switch (prog->expected_attach_type) { |
---|
| 4463 | + case BPF_LSM_MAC: |
---|
| 4464 | + case BPF_TRACE_FEXIT: |
---|
| 4465 | + /* When LSM programs are attached to void LSM hooks |
---|
| 4466 | + * they use FEXIT trampolines and when attached to |
---|
| 4467 | + * int LSM hooks, they use MODIFY_RETURN trampolines. |
---|
| 4468 | + * |
---|
| 4469 | + * While the LSM programs are BPF_MODIFY_RETURN-like |
---|
| 4470 | + * the check: |
---|
| 4471 | + * |
---|
| 4472 | + * if (ret_type != 'int') |
---|
| 4473 | + * return -EINVAL; |
---|
| 4474 | + * |
---|
| 4475 | + * is _not_ done here. This is still safe as LSM hooks |
---|
| 4476 | + * have only void and int return types. |
---|
| 4477 | + */ |
---|
| 4478 | + if (!t) |
---|
| 4479 | + return true; |
---|
| 4480 | + t = btf_type_by_id(btf, t->type); |
---|
| 4481 | + break; |
---|
| 4482 | + case BPF_MODIFY_RETURN: |
---|
| 4483 | + /* For now the BPF_MODIFY_RETURN can only be attached to |
---|
| 4484 | + * functions that return an int. |
---|
| 4485 | + */ |
---|
| 4486 | + if (!t) |
---|
| 4487 | + return false; |
---|
| 4488 | + |
---|
| 4489 | + t = btf_type_skip_modifiers(btf, t->type, NULL); |
---|
| 4490 | + if (!btf_type_is_small_int(t)) { |
---|
| 4491 | + bpf_log(log, |
---|
| 4492 | + "ret type %s not allowed for fmod_ret\n", |
---|
| 4493 | + btf_kind_str[BTF_INFO_KIND(t->info)]); |
---|
| 4494 | + return false; |
---|
| 4495 | + } |
---|
| 4496 | + break; |
---|
| 4497 | + default: |
---|
| 4498 | + bpf_log(log, "func '%s' doesn't have %d-th argument\n", |
---|
| 4499 | + tname, arg + 1); |
---|
| 4500 | + return false; |
---|
| 4501 | + } |
---|
| 4502 | + } else { |
---|
| 4503 | + if (!t) |
---|
| 4504 | + /* Default prog with 5 args */ |
---|
| 4505 | + return true; |
---|
| 4506 | + t = btf_type_by_id(btf, args[arg].type); |
---|
| 4507 | + } |
---|
| 4508 | + |
---|
| 4509 | + /* skip modifiers */ |
---|
| 4510 | + while (btf_type_is_modifier(t)) |
---|
| 4511 | + t = btf_type_by_id(btf, t->type); |
---|
| 4512 | + if (btf_type_is_small_int(t) || btf_type_is_enum(t)) |
---|
| 4513 | + /* accessing a scalar */ |
---|
| 4514 | + return true; |
---|
| 4515 | + if (!btf_type_is_ptr(t)) { |
---|
| 4516 | + bpf_log(log, |
---|
| 4517 | + "func '%s' arg%d '%s' has type %s. Only pointer access is allowed\n", |
---|
| 4518 | + tname, arg, |
---|
| 4519 | + __btf_name_by_offset(btf, t->name_off), |
---|
| 4520 | + btf_kind_str[BTF_INFO_KIND(t->info)]); |
---|
| 4521 | + return false; |
---|
| 4522 | + } |
---|
| 4523 | + |
---|
| 4524 | + /* check for PTR_TO_RDONLY_BUF_OR_NULL or PTR_TO_RDWR_BUF_OR_NULL */ |
---|
| 4525 | + for (i = 0; i < prog->aux->ctx_arg_info_size; i++) { |
---|
| 4526 | + const struct bpf_ctx_arg_aux *ctx_arg_info = &prog->aux->ctx_arg_info[i]; |
---|
| 4527 | + |
---|
| 4528 | + if (ctx_arg_info->offset == off && |
---|
| 4529 | + (ctx_arg_info->reg_type == PTR_TO_RDONLY_BUF_OR_NULL || |
---|
| 4530 | + ctx_arg_info->reg_type == PTR_TO_RDWR_BUF_OR_NULL)) { |
---|
| 4531 | + info->reg_type = ctx_arg_info->reg_type; |
---|
| 4532 | + return true; |
---|
| 4533 | + } |
---|
| 4534 | + } |
---|
| 4535 | + |
---|
| 4536 | + if (t->type == 0) |
---|
| 4537 | + /* This is a pointer to void. |
---|
| 4538 | + * It is the same as scalar from the verifier safety pov. |
---|
| 4539 | + * No further pointer walking is allowed. |
---|
| 4540 | + */ |
---|
| 4541 | + return true; |
---|
| 4542 | + |
---|
| 4543 | + if (is_string_ptr(btf, t)) |
---|
| 4544 | + return true; |
---|
| 4545 | + |
---|
| 4546 | + /* this is a pointer to another type */ |
---|
| 4547 | + for (i = 0; i < prog->aux->ctx_arg_info_size; i++) { |
---|
| 4548 | + const struct bpf_ctx_arg_aux *ctx_arg_info = &prog->aux->ctx_arg_info[i]; |
---|
| 4549 | + |
---|
| 4550 | + if (ctx_arg_info->offset == off) { |
---|
| 4551 | + info->reg_type = ctx_arg_info->reg_type; |
---|
| 4552 | + info->btf_id = ctx_arg_info->btf_id; |
---|
| 4553 | + return true; |
---|
| 4554 | + } |
---|
| 4555 | + } |
---|
| 4556 | + |
---|
| 4557 | + info->reg_type = PTR_TO_BTF_ID; |
---|
| 4558 | + if (tgt_prog) { |
---|
| 4559 | + enum bpf_prog_type tgt_type; |
---|
| 4560 | + |
---|
| 4561 | + if (tgt_prog->type == BPF_PROG_TYPE_EXT) |
---|
| 4562 | + tgt_type = tgt_prog->aux->saved_dst_prog_type; |
---|
| 4563 | + else |
---|
| 4564 | + tgt_type = tgt_prog->type; |
---|
| 4565 | + |
---|
| 4566 | + ret = btf_translate_to_vmlinux(log, btf, t, tgt_type, arg); |
---|
| 4567 | + if (ret > 0) { |
---|
| 4568 | + info->btf_id = ret; |
---|
| 4569 | + return true; |
---|
| 4570 | + } else { |
---|
| 4571 | + return false; |
---|
| 4572 | + } |
---|
| 4573 | + } |
---|
| 4574 | + |
---|
| 4575 | + info->btf_id = t->type; |
---|
| 4576 | + t = btf_type_by_id(btf, t->type); |
---|
| 4577 | + /* skip modifiers */ |
---|
| 4578 | + while (btf_type_is_modifier(t)) { |
---|
| 4579 | + info->btf_id = t->type; |
---|
| 4580 | + t = btf_type_by_id(btf, t->type); |
---|
| 4581 | + } |
---|
| 4582 | + if (!btf_type_is_struct(t)) { |
---|
| 4583 | + bpf_log(log, |
---|
| 4584 | + "func '%s' arg%d type %s is not a struct\n", |
---|
| 4585 | + tname, arg, btf_kind_str[BTF_INFO_KIND(t->info)]); |
---|
| 4586 | + return false; |
---|
| 4587 | + } |
---|
| 4588 | + bpf_log(log, "func '%s' arg%d has btf_id %d type %s '%s'\n", |
---|
| 4589 | + tname, arg, info->btf_id, btf_kind_str[BTF_INFO_KIND(t->info)], |
---|
| 4590 | + __btf_name_by_offset(btf, t->name_off)); |
---|
| 4591 | + return true; |
---|
| 4592 | +} |
---|
| 4593 | + |
---|
| 4594 | +enum bpf_struct_walk_result { |
---|
| 4595 | + /* < 0 error */ |
---|
| 4596 | + WALK_SCALAR = 0, |
---|
| 4597 | + WALK_PTR, |
---|
| 4598 | + WALK_STRUCT, |
---|
| 4599 | +}; |
---|
| 4600 | + |
---|
| 4601 | +static int btf_struct_walk(struct bpf_verifier_log *log, |
---|
| 4602 | + const struct btf_type *t, int off, int size, |
---|
| 4603 | + u32 *next_btf_id) |
---|
| 4604 | +{ |
---|
| 4605 | + u32 i, moff, mtrue_end, msize = 0, total_nelems = 0; |
---|
| 4606 | + const struct btf_type *mtype, *elem_type = NULL; |
---|
| 4607 | + const struct btf_member *member; |
---|
| 4608 | + const char *tname, *mname; |
---|
| 4609 | + u32 vlen, elem_id, mid; |
---|
| 4610 | + |
---|
| 4611 | +again: |
---|
| 4612 | + tname = __btf_name_by_offset(btf_vmlinux, t->name_off); |
---|
| 4613 | + if (!btf_type_is_struct(t)) { |
---|
| 4614 | + bpf_log(log, "Type '%s' is not a struct\n", tname); |
---|
| 4615 | + return -EINVAL; |
---|
| 4616 | + } |
---|
| 4617 | + |
---|
| 4618 | + vlen = btf_type_vlen(t); |
---|
| 4619 | + if (off + size > t->size) { |
---|
| 4620 | + /* If the last element is a variable size array, we may |
---|
| 4621 | + * need to relax the rule. |
---|
| 4622 | + */ |
---|
| 4623 | + struct btf_array *array_elem; |
---|
| 4624 | + |
---|
| 4625 | + if (vlen == 0) |
---|
| 4626 | + goto error; |
---|
| 4627 | + |
---|
| 4628 | + member = btf_type_member(t) + vlen - 1; |
---|
| 4629 | + mtype = btf_type_skip_modifiers(btf_vmlinux, member->type, |
---|
| 4630 | + NULL); |
---|
| 4631 | + if (!btf_type_is_array(mtype)) |
---|
| 4632 | + goto error; |
---|
| 4633 | + |
---|
| 4634 | + array_elem = (struct btf_array *)(mtype + 1); |
---|
| 4635 | + if (array_elem->nelems != 0) |
---|
| 4636 | + goto error; |
---|
| 4637 | + |
---|
| 4638 | + moff = btf_member_bit_offset(t, member) / 8; |
---|
| 4639 | + if (off < moff) |
---|
| 4640 | + goto error; |
---|
| 4641 | + |
---|
| 4642 | + /* Only allow structure for now, can be relaxed for |
---|
| 4643 | + * other types later. |
---|
| 4644 | + */ |
---|
| 4645 | + t = btf_type_skip_modifiers(btf_vmlinux, array_elem->type, |
---|
| 4646 | + NULL); |
---|
| 4647 | + if (!btf_type_is_struct(t)) |
---|
| 4648 | + goto error; |
---|
| 4649 | + |
---|
| 4650 | + off = (off - moff) % t->size; |
---|
| 4651 | + goto again; |
---|
| 4652 | + |
---|
| 4653 | +error: |
---|
| 4654 | + bpf_log(log, "access beyond struct %s at off %u size %u\n", |
---|
| 4655 | + tname, off, size); |
---|
| 4656 | + return -EACCES; |
---|
| 4657 | + } |
---|
| 4658 | + |
---|
| 4659 | + for_each_member(i, t, member) { |
---|
| 4660 | + /* offset of the field in bytes */ |
---|
| 4661 | + moff = btf_member_bit_offset(t, member) / 8; |
---|
| 4662 | + if (off + size <= moff) |
---|
| 4663 | + /* won't find anything, field is already too far */ |
---|
| 4664 | + break; |
---|
| 4665 | + |
---|
| 4666 | + if (btf_member_bitfield_size(t, member)) { |
---|
| 4667 | + u32 end_bit = btf_member_bit_offset(t, member) + |
---|
| 4668 | + btf_member_bitfield_size(t, member); |
---|
| 4669 | + |
---|
| 4670 | + /* off <= moff instead of off == moff because clang |
---|
| 4671 | + * does not generate a BTF member for anonymous |
---|
| 4672 | + * bitfield like the ":16" here: |
---|
| 4673 | + * struct { |
---|
| 4674 | + * int :16; |
---|
| 4675 | + * int x:8; |
---|
| 4676 | + * }; |
---|
| 4677 | + */ |
---|
| 4678 | + if (off <= moff && |
---|
| 4679 | + BITS_ROUNDUP_BYTES(end_bit) <= off + size) |
---|
| 4680 | + return WALK_SCALAR; |
---|
| 4681 | + |
---|
| 4682 | + /* off may be accessing a following member |
---|
| 4683 | + * |
---|
| 4684 | + * or |
---|
| 4685 | + * |
---|
| 4686 | + * Doing partial access at either end of this |
---|
| 4687 | + * bitfield. Continue on this case also to |
---|
| 4688 | + * treat it as not accessing this bitfield |
---|
| 4689 | + * and eventually error out as field not |
---|
| 4690 | + * found to keep it simple. |
---|
| 4691 | + * It could be relaxed if there was a legit |
---|
| 4692 | + * partial access case later. |
---|
| 4693 | + */ |
---|
| 4694 | + continue; |
---|
| 4695 | + } |
---|
| 4696 | + |
---|
| 4697 | + /* In case of "off" is pointing to holes of a struct */ |
---|
| 4698 | + if (off < moff) |
---|
| 4699 | + break; |
---|
| 4700 | + |
---|
| 4701 | + /* type of the field */ |
---|
| 4702 | + mid = member->type; |
---|
| 4703 | + mtype = btf_type_by_id(btf_vmlinux, member->type); |
---|
| 4704 | + mname = __btf_name_by_offset(btf_vmlinux, member->name_off); |
---|
| 4705 | + |
---|
| 4706 | + mtype = __btf_resolve_size(btf_vmlinux, mtype, &msize, |
---|
| 4707 | + &elem_type, &elem_id, &total_nelems, |
---|
| 4708 | + &mid); |
---|
| 4709 | + if (IS_ERR(mtype)) { |
---|
| 4710 | + bpf_log(log, "field %s doesn't have size\n", mname); |
---|
| 4711 | + return -EFAULT; |
---|
| 4712 | + } |
---|
| 4713 | + |
---|
| 4714 | + mtrue_end = moff + msize; |
---|
| 4715 | + if (off >= mtrue_end) |
---|
| 4716 | + /* no overlap with member, keep iterating */ |
---|
| 4717 | + continue; |
---|
| 4718 | + |
---|
| 4719 | + if (btf_type_is_array(mtype)) { |
---|
| 4720 | + u32 elem_idx; |
---|
| 4721 | + |
---|
| 4722 | + /* __btf_resolve_size() above helps to |
---|
| 4723 | + * linearize a multi-dimensional array. |
---|
| 4724 | + * |
---|
| 4725 | + * The logic here is treating an array |
---|
| 4726 | + * in a struct as the following way: |
---|
| 4727 | + * |
---|
| 4728 | + * struct outer { |
---|
| 4729 | + * struct inner array[2][2]; |
---|
| 4730 | + * }; |
---|
| 4731 | + * |
---|
| 4732 | + * looks like: |
---|
| 4733 | + * |
---|
| 4734 | + * struct outer { |
---|
| 4735 | + * struct inner array_elem0; |
---|
| 4736 | + * struct inner array_elem1; |
---|
| 4737 | + * struct inner array_elem2; |
---|
| 4738 | + * struct inner array_elem3; |
---|
| 4739 | + * }; |
---|
| 4740 | + * |
---|
| 4741 | + * When accessing outer->array[1][0], it moves |
---|
| 4742 | + * moff to "array_elem2", set mtype to |
---|
| 4743 | + * "struct inner", and msize also becomes |
---|
| 4744 | + * sizeof(struct inner). Then most of the |
---|
| 4745 | + * remaining logic will fall through without |
---|
| 4746 | + * caring the current member is an array or |
---|
| 4747 | + * not. |
---|
| 4748 | + * |
---|
| 4749 | + * Unlike mtype/msize/moff, mtrue_end does not |
---|
| 4750 | + * change. The naming difference ("_true") tells |
---|
| 4751 | + * that it is not always corresponding to |
---|
| 4752 | + * the current mtype/msize/moff. |
---|
| 4753 | + * It is the true end of the current |
---|
| 4754 | + * member (i.e. array in this case). That |
---|
| 4755 | + * will allow an int array to be accessed like |
---|
| 4756 | + * a scratch space, |
---|
| 4757 | + * i.e. allow access beyond the size of |
---|
| 4758 | + * the array's element as long as it is |
---|
| 4759 | + * within the mtrue_end boundary. |
---|
| 4760 | + */ |
---|
| 4761 | + |
---|
| 4762 | + /* skip empty array */ |
---|
| 4763 | + if (moff == mtrue_end) |
---|
| 4764 | + continue; |
---|
| 4765 | + |
---|
| 4766 | + msize /= total_nelems; |
---|
| 4767 | + elem_idx = (off - moff) / msize; |
---|
| 4768 | + moff += elem_idx * msize; |
---|
| 4769 | + mtype = elem_type; |
---|
| 4770 | + mid = elem_id; |
---|
| 4771 | + } |
---|
| 4772 | + |
---|
| 4773 | + /* the 'off' we're looking for is either equal to start |
---|
| 4774 | + * of this field or inside of this struct |
---|
| 4775 | + */ |
---|
| 4776 | + if (btf_type_is_struct(mtype)) { |
---|
| 4777 | + /* our field must be inside that union or struct */ |
---|
| 4778 | + t = mtype; |
---|
| 4779 | + |
---|
| 4780 | + /* return if the offset matches the member offset */ |
---|
| 4781 | + if (off == moff) { |
---|
| 4782 | + *next_btf_id = mid; |
---|
| 4783 | + return WALK_STRUCT; |
---|
| 4784 | + } |
---|
| 4785 | + |
---|
| 4786 | + /* adjust offset we're looking for */ |
---|
| 4787 | + off -= moff; |
---|
| 4788 | + goto again; |
---|
| 4789 | + } |
---|
| 4790 | + |
---|
| 4791 | + if (btf_type_is_ptr(mtype)) { |
---|
| 4792 | + const struct btf_type *stype; |
---|
| 4793 | + u32 id; |
---|
| 4794 | + |
---|
| 4795 | + if (msize != size || off != moff) { |
---|
| 4796 | + bpf_log(log, |
---|
| 4797 | + "cannot access ptr member %s with moff %u in struct %s with off %u size %u\n", |
---|
| 4798 | + mname, moff, tname, off, size); |
---|
| 4799 | + return -EACCES; |
---|
| 4800 | + } |
---|
| 4801 | + stype = btf_type_skip_modifiers(btf_vmlinux, mtype->type, &id); |
---|
| 4802 | + if (btf_type_is_struct(stype)) { |
---|
| 4803 | + *next_btf_id = id; |
---|
| 4804 | + return WALK_PTR; |
---|
| 4805 | + } |
---|
| 4806 | + } |
---|
| 4807 | + |
---|
| 4808 | + /* Allow more flexible access within an int as long as |
---|
| 4809 | + * it is within mtrue_end. |
---|
| 4810 | + * Since mtrue_end could be the end of an array, |
---|
| 4811 | + * that also allows using an array of int as a scratch |
---|
| 4812 | + * space. e.g. skb->cb[]. |
---|
| 4813 | + */ |
---|
| 4814 | + if (off + size > mtrue_end) { |
---|
| 4815 | + bpf_log(log, |
---|
| 4816 | + "access beyond the end of member %s (mend:%u) in struct %s with off %u size %u\n", |
---|
| 4817 | + mname, mtrue_end, tname, off, size); |
---|
| 4818 | + return -EACCES; |
---|
| 4819 | + } |
---|
| 4820 | + |
---|
| 4821 | + return WALK_SCALAR; |
---|
| 4822 | + } |
---|
| 4823 | + bpf_log(log, "struct %s doesn't have field at offset %d\n", tname, off); |
---|
| 4824 | + return -EINVAL; |
---|
| 4825 | +} |
---|
| 4826 | + |
---|
| 4827 | +int btf_struct_access(struct bpf_verifier_log *log, |
---|
| 4828 | + const struct btf_type *t, int off, int size, |
---|
| 4829 | + enum bpf_access_type atype __maybe_unused, |
---|
| 4830 | + u32 *next_btf_id) |
---|
| 4831 | +{ |
---|
| 4832 | + int err; |
---|
| 4833 | + u32 id; |
---|
| 4834 | + |
---|
| 4835 | + do { |
---|
| 4836 | + err = btf_struct_walk(log, t, off, size, &id); |
---|
| 4837 | + |
---|
| 4838 | + switch (err) { |
---|
| 4839 | + case WALK_PTR: |
---|
| 4840 | + /* If we found the pointer or scalar on t+off, |
---|
| 4841 | + * we're done. |
---|
| 4842 | + */ |
---|
| 4843 | + *next_btf_id = id; |
---|
| 4844 | + return PTR_TO_BTF_ID; |
---|
| 4845 | + case WALK_SCALAR: |
---|
| 4846 | + return SCALAR_VALUE; |
---|
| 4847 | + case WALK_STRUCT: |
---|
| 4848 | + /* We found nested struct, so continue the search |
---|
| 4849 | + * by diving in it. At this point the offset is |
---|
| 4850 | + * aligned with the new type, so set it to 0. |
---|
| 4851 | + */ |
---|
| 4852 | + t = btf_type_by_id(btf_vmlinux, id); |
---|
| 4853 | + off = 0; |
---|
| 4854 | + break; |
---|
| 4855 | + default: |
---|
| 4856 | + /* It's either error or unknown return value.. |
---|
| 4857 | + * scream and leave. |
---|
| 4858 | + */ |
---|
| 4859 | + if (WARN_ONCE(err > 0, "unknown btf_struct_walk return value")) |
---|
| 4860 | + return -EINVAL; |
---|
| 4861 | + return err; |
---|
| 4862 | + } |
---|
| 4863 | + } while (t); |
---|
| 4864 | + |
---|
| 4865 | + return -EINVAL; |
---|
| 4866 | +} |
---|
| 4867 | + |
---|
| 4868 | +bool btf_struct_ids_match(struct bpf_verifier_log *log, |
---|
| 4869 | + int off, u32 id, u32 need_type_id) |
---|
| 4870 | +{ |
---|
| 4871 | + const struct btf_type *type; |
---|
| 4872 | + int err; |
---|
| 4873 | + |
---|
| 4874 | + /* Are we already done? */ |
---|
| 4875 | + if (need_type_id == id && off == 0) |
---|
| 4876 | + return true; |
---|
| 4877 | + |
---|
| 4878 | +again: |
---|
| 4879 | + type = btf_type_by_id(btf_vmlinux, id); |
---|
| 4880 | + if (!type) |
---|
| 4881 | + return false; |
---|
| 4882 | + err = btf_struct_walk(log, type, off, 1, &id); |
---|
| 4883 | + if (err != WALK_STRUCT) |
---|
| 4884 | + return false; |
---|
| 4885 | + |
---|
| 4886 | + /* We found nested struct object. If it matches |
---|
| 4887 | + * the requested ID, we're done. Otherwise let's |
---|
| 4888 | + * continue the search with offset 0 in the new |
---|
| 4889 | + * type. |
---|
| 4890 | + */ |
---|
| 4891 | + if (need_type_id != id) { |
---|
| 4892 | + off = 0; |
---|
| 4893 | + goto again; |
---|
| 4894 | + } |
---|
| 4895 | + |
---|
| 4896 | + return true; |
---|
| 4897 | +} |
---|
| 4898 | + |
---|
| 4899 | +static int __get_type_size(struct btf *btf, u32 btf_id, |
---|
| 4900 | + const struct btf_type **bad_type) |
---|
| 4901 | +{ |
---|
| 4902 | + const struct btf_type *t; |
---|
| 4903 | + |
---|
| 4904 | + if (!btf_id) |
---|
| 4905 | + /* void */ |
---|
| 4906 | + return 0; |
---|
| 4907 | + t = btf_type_by_id(btf, btf_id); |
---|
| 4908 | + while (t && btf_type_is_modifier(t)) |
---|
| 4909 | + t = btf_type_by_id(btf, t->type); |
---|
| 4910 | + if (!t) { |
---|
| 4911 | + *bad_type = btf->types[0]; |
---|
| 4912 | + return -EINVAL; |
---|
| 4913 | + } |
---|
| 4914 | + if (btf_type_is_ptr(t)) |
---|
| 4915 | + /* kernel size of pointer. Not BPF's size of pointer*/ |
---|
| 4916 | + return sizeof(void *); |
---|
| 4917 | + if (btf_type_is_int(t) || btf_type_is_enum(t)) |
---|
| 4918 | + return t->size; |
---|
| 4919 | + *bad_type = t; |
---|
| 4920 | + return -EINVAL; |
---|
| 4921 | +} |
---|
| 4922 | + |
---|
| 4923 | +int btf_distill_func_proto(struct bpf_verifier_log *log, |
---|
| 4924 | + struct btf *btf, |
---|
| 4925 | + const struct btf_type *func, |
---|
| 4926 | + const char *tname, |
---|
| 4927 | + struct btf_func_model *m) |
---|
| 4928 | +{ |
---|
| 4929 | + const struct btf_param *args; |
---|
| 4930 | + const struct btf_type *t; |
---|
| 4931 | + u32 i, nargs; |
---|
| 4932 | + int ret; |
---|
| 4933 | + |
---|
| 4934 | + if (!func) { |
---|
| 4935 | + /* BTF function prototype doesn't match the verifier types. |
---|
| 4936 | + * Fall back to 5 u64 args. |
---|
| 4937 | + */ |
---|
| 4938 | + for (i = 0; i < 5; i++) |
---|
| 4939 | + m->arg_size[i] = 8; |
---|
| 4940 | + m->ret_size = 8; |
---|
| 4941 | + m->nr_args = 5; |
---|
| 4942 | + return 0; |
---|
| 4943 | + } |
---|
| 4944 | + args = (const struct btf_param *)(func + 1); |
---|
| 4945 | + nargs = btf_type_vlen(func); |
---|
| 4946 | + if (nargs >= MAX_BPF_FUNC_ARGS) { |
---|
| 4947 | + bpf_log(log, |
---|
| 4948 | + "The function %s has %d arguments. Too many.\n", |
---|
| 4949 | + tname, nargs); |
---|
| 4950 | + return -EINVAL; |
---|
| 4951 | + } |
---|
| 4952 | + ret = __get_type_size(btf, func->type, &t); |
---|
| 4953 | + if (ret < 0) { |
---|
| 4954 | + bpf_log(log, |
---|
| 4955 | + "The function %s return type %s is unsupported.\n", |
---|
| 4956 | + tname, btf_kind_str[BTF_INFO_KIND(t->info)]); |
---|
| 4957 | + return -EINVAL; |
---|
| 4958 | + } |
---|
| 4959 | + m->ret_size = ret; |
---|
| 4960 | + |
---|
| 4961 | + for (i = 0; i < nargs; i++) { |
---|
| 4962 | + if (i == nargs - 1 && args[i].type == 0) { |
---|
| 4963 | + bpf_log(log, |
---|
| 4964 | + "The function %s with variable args is unsupported.\n", |
---|
| 4965 | + tname); |
---|
| 4966 | + return -EINVAL; |
---|
| 4967 | + } |
---|
| 4968 | + ret = __get_type_size(btf, args[i].type, &t); |
---|
| 4969 | + if (ret < 0) { |
---|
| 4970 | + bpf_log(log, |
---|
| 4971 | + "The function %s arg%d type %s is unsupported.\n", |
---|
| 4972 | + tname, i, btf_kind_str[BTF_INFO_KIND(t->info)]); |
---|
| 4973 | + return -EINVAL; |
---|
| 4974 | + } |
---|
| 4975 | + if (ret == 0) { |
---|
| 4976 | + bpf_log(log, |
---|
| 4977 | + "The function %s has malformed void argument.\n", |
---|
| 4978 | + tname); |
---|
| 4979 | + return -EINVAL; |
---|
| 4980 | + } |
---|
| 4981 | + m->arg_size[i] = ret; |
---|
| 4982 | + } |
---|
| 4983 | + m->nr_args = nargs; |
---|
| 4984 | + return 0; |
---|
| 4985 | +} |
---|
| 4986 | + |
---|
| 4987 | +/* Compare BTFs of two functions assuming only scalars and pointers to context. |
---|
| 4988 | + * t1 points to BTF_KIND_FUNC in btf1 |
---|
| 4989 | + * t2 points to BTF_KIND_FUNC in btf2 |
---|
| 4990 | + * Returns: |
---|
| 4991 | + * EINVAL - function prototype mismatch |
---|
| 4992 | + * EFAULT - verifier bug |
---|
| 4993 | + * 0 - 99% match. The last 1% is validated by the verifier. |
---|
| 4994 | + */ |
---|
| 4995 | +static int btf_check_func_type_match(struct bpf_verifier_log *log, |
---|
| 4996 | + struct btf *btf1, const struct btf_type *t1, |
---|
| 4997 | + struct btf *btf2, const struct btf_type *t2) |
---|
| 4998 | +{ |
---|
| 4999 | + const struct btf_param *args1, *args2; |
---|
| 5000 | + const char *fn1, *fn2, *s1, *s2; |
---|
| 5001 | + u32 nargs1, nargs2, i; |
---|
| 5002 | + |
---|
| 5003 | + fn1 = btf_name_by_offset(btf1, t1->name_off); |
---|
| 5004 | + fn2 = btf_name_by_offset(btf2, t2->name_off); |
---|
| 5005 | + |
---|
| 5006 | + if (btf_func_linkage(t1) != BTF_FUNC_GLOBAL) { |
---|
| 5007 | + bpf_log(log, "%s() is not a global function\n", fn1); |
---|
| 5008 | + return -EINVAL; |
---|
| 5009 | + } |
---|
| 5010 | + if (btf_func_linkage(t2) != BTF_FUNC_GLOBAL) { |
---|
| 5011 | + bpf_log(log, "%s() is not a global function\n", fn2); |
---|
| 5012 | + return -EINVAL; |
---|
| 5013 | + } |
---|
| 5014 | + |
---|
| 5015 | + t1 = btf_type_by_id(btf1, t1->type); |
---|
| 5016 | + if (!t1 || !btf_type_is_func_proto(t1)) |
---|
| 5017 | + return -EFAULT; |
---|
| 5018 | + t2 = btf_type_by_id(btf2, t2->type); |
---|
| 5019 | + if (!t2 || !btf_type_is_func_proto(t2)) |
---|
| 5020 | + return -EFAULT; |
---|
| 5021 | + |
---|
| 5022 | + args1 = (const struct btf_param *)(t1 + 1); |
---|
| 5023 | + nargs1 = btf_type_vlen(t1); |
---|
| 5024 | + args2 = (const struct btf_param *)(t2 + 1); |
---|
| 5025 | + nargs2 = btf_type_vlen(t2); |
---|
| 5026 | + |
---|
| 5027 | + if (nargs1 != nargs2) { |
---|
| 5028 | + bpf_log(log, "%s() has %d args while %s() has %d args\n", |
---|
| 5029 | + fn1, nargs1, fn2, nargs2); |
---|
| 5030 | + return -EINVAL; |
---|
| 5031 | + } |
---|
| 5032 | + |
---|
| 5033 | + t1 = btf_type_skip_modifiers(btf1, t1->type, NULL); |
---|
| 5034 | + t2 = btf_type_skip_modifiers(btf2, t2->type, NULL); |
---|
| 5035 | + if (t1->info != t2->info) { |
---|
| 5036 | + bpf_log(log, |
---|
| 5037 | + "Return type %s of %s() doesn't match type %s of %s()\n", |
---|
| 5038 | + btf_type_str(t1), fn1, |
---|
| 5039 | + btf_type_str(t2), fn2); |
---|
| 5040 | + return -EINVAL; |
---|
| 5041 | + } |
---|
| 5042 | + |
---|
| 5043 | + for (i = 0; i < nargs1; i++) { |
---|
| 5044 | + t1 = btf_type_skip_modifiers(btf1, args1[i].type, NULL); |
---|
| 5045 | + t2 = btf_type_skip_modifiers(btf2, args2[i].type, NULL); |
---|
| 5046 | + |
---|
| 5047 | + if (t1->info != t2->info) { |
---|
| 5048 | + bpf_log(log, "arg%d in %s() is %s while %s() has %s\n", |
---|
| 5049 | + i, fn1, btf_type_str(t1), |
---|
| 5050 | + fn2, btf_type_str(t2)); |
---|
| 5051 | + return -EINVAL; |
---|
| 5052 | + } |
---|
| 5053 | + if (btf_type_has_size(t1) && t1->size != t2->size) { |
---|
| 5054 | + bpf_log(log, |
---|
| 5055 | + "arg%d in %s() has size %d while %s() has %d\n", |
---|
| 5056 | + i, fn1, t1->size, |
---|
| 5057 | + fn2, t2->size); |
---|
| 5058 | + return -EINVAL; |
---|
| 5059 | + } |
---|
| 5060 | + |
---|
| 5061 | + /* global functions are validated with scalars and pointers |
---|
| 5062 | + * to context only. And only global functions can be replaced. |
---|
| 5063 | + * Hence type check only those types. |
---|
| 5064 | + */ |
---|
| 5065 | + if (btf_type_is_int(t1) || btf_type_is_enum(t1)) |
---|
| 5066 | + continue; |
---|
| 5067 | + if (!btf_type_is_ptr(t1)) { |
---|
| 5068 | + bpf_log(log, |
---|
| 5069 | + "arg%d in %s() has unrecognized type\n", |
---|
| 5070 | + i, fn1); |
---|
| 5071 | + return -EINVAL; |
---|
| 5072 | + } |
---|
| 5073 | + t1 = btf_type_skip_modifiers(btf1, t1->type, NULL); |
---|
| 5074 | + t2 = btf_type_skip_modifiers(btf2, t2->type, NULL); |
---|
| 5075 | + if (!btf_type_is_struct(t1)) { |
---|
| 5076 | + bpf_log(log, |
---|
| 5077 | + "arg%d in %s() is not a pointer to context\n", |
---|
| 5078 | + i, fn1); |
---|
| 5079 | + return -EINVAL; |
---|
| 5080 | + } |
---|
| 5081 | + if (!btf_type_is_struct(t2)) { |
---|
| 5082 | + bpf_log(log, |
---|
| 5083 | + "arg%d in %s() is not a pointer to context\n", |
---|
| 5084 | + i, fn2); |
---|
| 5085 | + return -EINVAL; |
---|
| 5086 | + } |
---|
| 5087 | + /* This is an optional check to make program writing easier. |
---|
| 5088 | + * Compare names of structs and report an error to the user. |
---|
| 5089 | + * btf_prepare_func_args() already checked that t2 struct |
---|
| 5090 | + * is a context type. btf_prepare_func_args() will check |
---|
| 5091 | + * later that t1 struct is a context type as well. |
---|
| 5092 | + */ |
---|
| 5093 | + s1 = btf_name_by_offset(btf1, t1->name_off); |
---|
| 5094 | + s2 = btf_name_by_offset(btf2, t2->name_off); |
---|
| 5095 | + if (strcmp(s1, s2)) { |
---|
| 5096 | + bpf_log(log, |
---|
| 5097 | + "arg%d %s(struct %s *) doesn't match %s(struct %s *)\n", |
---|
| 5098 | + i, fn1, s1, fn2, s2); |
---|
| 5099 | + return -EINVAL; |
---|
| 5100 | + } |
---|
| 5101 | + } |
---|
| 5102 | + return 0; |
---|
| 5103 | +} |
---|
| 5104 | + |
---|
| 5105 | +/* Compare BTFs of given program with BTF of target program */ |
---|
| 5106 | +int btf_check_type_match(struct bpf_verifier_log *log, const struct bpf_prog *prog, |
---|
| 5107 | + struct btf *btf2, const struct btf_type *t2) |
---|
| 5108 | +{ |
---|
| 5109 | + struct btf *btf1 = prog->aux->btf; |
---|
| 5110 | + const struct btf_type *t1; |
---|
| 5111 | + u32 btf_id = 0; |
---|
| 5112 | + |
---|
| 5113 | + if (!prog->aux->func_info) { |
---|
| 5114 | + bpf_log(log, "Program extension requires BTF\n"); |
---|
| 5115 | + return -EINVAL; |
---|
| 5116 | + } |
---|
| 5117 | + |
---|
| 5118 | + btf_id = prog->aux->func_info[0].type_id; |
---|
| 5119 | + if (!btf_id) |
---|
| 5120 | + return -EFAULT; |
---|
| 5121 | + |
---|
| 5122 | + t1 = btf_type_by_id(btf1, btf_id); |
---|
| 5123 | + if (!t1 || !btf_type_is_func(t1)) |
---|
| 5124 | + return -EFAULT; |
---|
| 5125 | + |
---|
| 5126 | + return btf_check_func_type_match(log, btf1, t1, btf2, t2); |
---|
| 5127 | +} |
---|
| 5128 | + |
---|
| 5129 | +/* Compare BTF of a function with given bpf_reg_state. |
---|
| 5130 | + * Returns: |
---|
| 5131 | + * EFAULT - there is a verifier bug. Abort verification. |
---|
| 5132 | + * EINVAL - there is a type mismatch or BTF is not available. |
---|
| 5133 | + * 0 - BTF matches with what bpf_reg_state expects. |
---|
| 5134 | + * Only PTR_TO_CTX and SCALAR_VALUE states are recognized. |
---|
| 5135 | + */ |
---|
| 5136 | +int btf_check_func_arg_match(struct bpf_verifier_env *env, int subprog, |
---|
| 5137 | + struct bpf_reg_state *reg) |
---|
| 5138 | +{ |
---|
| 5139 | + struct bpf_verifier_log *log = &env->log; |
---|
| 5140 | + struct bpf_prog *prog = env->prog; |
---|
| 5141 | + struct btf *btf = prog->aux->btf; |
---|
| 5142 | + const struct btf_param *args; |
---|
| 5143 | + const struct btf_type *t; |
---|
| 5144 | + u32 i, nargs, btf_id; |
---|
| 5145 | + const char *tname; |
---|
| 5146 | + |
---|
| 5147 | + if (!prog->aux->func_info) |
---|
| 5148 | + return -EINVAL; |
---|
| 5149 | + |
---|
| 5150 | + btf_id = prog->aux->func_info[subprog].type_id; |
---|
| 5151 | + if (!btf_id) |
---|
| 5152 | + return -EFAULT; |
---|
| 5153 | + |
---|
| 5154 | + if (prog->aux->func_info_aux[subprog].unreliable) |
---|
| 5155 | + return -EINVAL; |
---|
| 5156 | + |
---|
| 5157 | + t = btf_type_by_id(btf, btf_id); |
---|
| 5158 | + if (!t || !btf_type_is_func(t)) { |
---|
| 5159 | + /* These checks were already done by the verifier while loading |
---|
| 5160 | + * struct bpf_func_info |
---|
| 5161 | + */ |
---|
| 5162 | + bpf_log(log, "BTF of func#%d doesn't point to KIND_FUNC\n", |
---|
| 5163 | + subprog); |
---|
| 5164 | + return -EFAULT; |
---|
| 5165 | + } |
---|
| 5166 | + tname = btf_name_by_offset(btf, t->name_off); |
---|
| 5167 | + |
---|
| 5168 | + t = btf_type_by_id(btf, t->type); |
---|
| 5169 | + if (!t || !btf_type_is_func_proto(t)) { |
---|
| 5170 | + bpf_log(log, "Invalid BTF of func %s\n", tname); |
---|
| 5171 | + return -EFAULT; |
---|
| 5172 | + } |
---|
| 5173 | + args = (const struct btf_param *)(t + 1); |
---|
| 5174 | + nargs = btf_type_vlen(t); |
---|
| 5175 | + if (nargs > 5) { |
---|
| 5176 | + bpf_log(log, "Function %s has %d > 5 args\n", tname, nargs); |
---|
| 5177 | + goto out; |
---|
| 5178 | + } |
---|
| 5179 | + /* check that BTF function arguments match actual types that the |
---|
| 5180 | + * verifier sees. |
---|
| 5181 | + */ |
---|
| 5182 | + for (i = 0; i < nargs; i++) { |
---|
| 5183 | + t = btf_type_by_id(btf, args[i].type); |
---|
| 5184 | + while (btf_type_is_modifier(t)) |
---|
| 5185 | + t = btf_type_by_id(btf, t->type); |
---|
| 5186 | + if (btf_type_is_int(t) || btf_type_is_enum(t)) { |
---|
| 5187 | + if (reg[i + 1].type == SCALAR_VALUE) |
---|
| 5188 | + continue; |
---|
| 5189 | + bpf_log(log, "R%d is not a scalar\n", i + 1); |
---|
| 5190 | + goto out; |
---|
| 5191 | + } |
---|
| 5192 | + if (btf_type_is_ptr(t)) { |
---|
| 5193 | + if (reg[i + 1].type == SCALAR_VALUE) { |
---|
| 5194 | + bpf_log(log, "R%d is not a pointer\n", i + 1); |
---|
| 5195 | + goto out; |
---|
| 5196 | + } |
---|
| 5197 | + /* If function expects ctx type in BTF check that caller |
---|
| 5198 | + * is passing PTR_TO_CTX. |
---|
| 5199 | + */ |
---|
| 5200 | + if (btf_get_prog_ctx_type(log, btf, t, prog->type, i)) { |
---|
| 5201 | + if (reg[i + 1].type != PTR_TO_CTX) { |
---|
| 5202 | + bpf_log(log, |
---|
| 5203 | + "arg#%d expected pointer to ctx, but got %s\n", |
---|
| 5204 | + i, btf_kind_str[BTF_INFO_KIND(t->info)]); |
---|
| 5205 | + goto out; |
---|
| 5206 | + } |
---|
| 5207 | + if (check_ctx_reg(env, ®[i + 1], i + 1)) |
---|
| 5208 | + goto out; |
---|
| 5209 | + continue; |
---|
| 5210 | + } |
---|
| 5211 | + } |
---|
| 5212 | + bpf_log(log, "Unrecognized arg#%d type %s\n", |
---|
| 5213 | + i, btf_kind_str[BTF_INFO_KIND(t->info)]); |
---|
| 5214 | + goto out; |
---|
| 5215 | + } |
---|
| 5216 | + return 0; |
---|
| 5217 | +out: |
---|
| 5218 | + /* Compiler optimizations can remove arguments from static functions |
---|
| 5219 | + * or mismatched type can be passed into a global function. |
---|
| 5220 | + * In such cases mark the function as unreliable from BTF point of view. |
---|
| 5221 | + */ |
---|
| 5222 | + prog->aux->func_info_aux[subprog].unreliable = true; |
---|
| 5223 | + return -EINVAL; |
---|
| 5224 | +} |
---|
| 5225 | + |
---|
| 5226 | +/* Convert BTF of a function into bpf_reg_state if possible |
---|
| 5227 | + * Returns: |
---|
| 5228 | + * EFAULT - there is a verifier bug. Abort verification. |
---|
| 5229 | + * EINVAL - cannot convert BTF. |
---|
| 5230 | + * 0 - Successfully converted BTF into bpf_reg_state |
---|
| 5231 | + * (either PTR_TO_CTX or SCALAR_VALUE). |
---|
| 5232 | + */ |
---|
| 5233 | +int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog, |
---|
| 5234 | + struct bpf_reg_state *reg) |
---|
| 5235 | +{ |
---|
| 5236 | + struct bpf_verifier_log *log = &env->log; |
---|
| 5237 | + struct bpf_prog *prog = env->prog; |
---|
| 5238 | + enum bpf_prog_type prog_type = prog->type; |
---|
| 5239 | + struct btf *btf = prog->aux->btf; |
---|
| 5240 | + const struct btf_param *args; |
---|
| 5241 | + const struct btf_type *t; |
---|
| 5242 | + u32 i, nargs, btf_id; |
---|
| 5243 | + const char *tname; |
---|
| 5244 | + |
---|
| 5245 | + if (!prog->aux->func_info || |
---|
| 5246 | + prog->aux->func_info_aux[subprog].linkage != BTF_FUNC_GLOBAL) { |
---|
| 5247 | + bpf_log(log, "Verifier bug\n"); |
---|
| 5248 | + return -EFAULT; |
---|
| 5249 | + } |
---|
| 5250 | + |
---|
| 5251 | + btf_id = prog->aux->func_info[subprog].type_id; |
---|
| 5252 | + if (!btf_id) { |
---|
| 5253 | + bpf_log(log, "Global functions need valid BTF\n"); |
---|
| 5254 | + return -EFAULT; |
---|
| 5255 | + } |
---|
| 5256 | + |
---|
| 5257 | + t = btf_type_by_id(btf, btf_id); |
---|
| 5258 | + if (!t || !btf_type_is_func(t)) { |
---|
| 5259 | + /* These checks were already done by the verifier while loading |
---|
| 5260 | + * struct bpf_func_info |
---|
| 5261 | + */ |
---|
| 5262 | + bpf_log(log, "BTF of func#%d doesn't point to KIND_FUNC\n", |
---|
| 5263 | + subprog); |
---|
| 5264 | + return -EFAULT; |
---|
| 5265 | + } |
---|
| 5266 | + tname = btf_name_by_offset(btf, t->name_off); |
---|
| 5267 | + |
---|
| 5268 | + if (log->level & BPF_LOG_LEVEL) |
---|
| 5269 | + bpf_log(log, "Validating %s() func#%d...\n", |
---|
| 5270 | + tname, subprog); |
---|
| 5271 | + |
---|
| 5272 | + if (prog->aux->func_info_aux[subprog].unreliable) { |
---|
| 5273 | + bpf_log(log, "Verifier bug in function %s()\n", tname); |
---|
| 5274 | + return -EFAULT; |
---|
| 5275 | + } |
---|
| 5276 | + if (prog_type == BPF_PROG_TYPE_EXT) |
---|
| 5277 | + prog_type = prog->aux->dst_prog->type; |
---|
| 5278 | + |
---|
| 5279 | + t = btf_type_by_id(btf, t->type); |
---|
| 5280 | + if (!t || !btf_type_is_func_proto(t)) { |
---|
| 5281 | + bpf_log(log, "Invalid type of function %s()\n", tname); |
---|
| 5282 | + return -EFAULT; |
---|
| 5283 | + } |
---|
| 5284 | + args = (const struct btf_param *)(t + 1); |
---|
| 5285 | + nargs = btf_type_vlen(t); |
---|
| 5286 | + if (nargs > 5) { |
---|
| 5287 | + bpf_log(log, "Global function %s() with %d > 5 args. Buggy compiler.\n", |
---|
| 5288 | + tname, nargs); |
---|
| 5289 | + return -EINVAL; |
---|
| 5290 | + } |
---|
| 5291 | + /* check that function returns int */ |
---|
| 5292 | + t = btf_type_by_id(btf, t->type); |
---|
| 5293 | + while (btf_type_is_modifier(t)) |
---|
| 5294 | + t = btf_type_by_id(btf, t->type); |
---|
| 5295 | + if (!btf_type_is_int(t) && !btf_type_is_enum(t)) { |
---|
| 5296 | + bpf_log(log, |
---|
| 5297 | + "Global function %s() doesn't return scalar. Only those are supported.\n", |
---|
| 5298 | + tname); |
---|
| 5299 | + return -EINVAL; |
---|
| 5300 | + } |
---|
| 5301 | + /* Convert BTF function arguments into verifier types. |
---|
| 5302 | + * Only PTR_TO_CTX and SCALAR are supported atm. |
---|
| 5303 | + */ |
---|
| 5304 | + for (i = 0; i < nargs; i++) { |
---|
| 5305 | + t = btf_type_by_id(btf, args[i].type); |
---|
| 5306 | + while (btf_type_is_modifier(t)) |
---|
| 5307 | + t = btf_type_by_id(btf, t->type); |
---|
| 5308 | + if (btf_type_is_int(t) || btf_type_is_enum(t)) { |
---|
| 5309 | + reg[i + 1].type = SCALAR_VALUE; |
---|
| 5310 | + continue; |
---|
| 5311 | + } |
---|
| 5312 | + if (btf_type_is_ptr(t) && |
---|
| 5313 | + btf_get_prog_ctx_type(log, btf, t, prog_type, i)) { |
---|
| 5314 | + reg[i + 1].type = PTR_TO_CTX; |
---|
| 5315 | + continue; |
---|
| 5316 | + } |
---|
| 5317 | + bpf_log(log, "Arg#%d type %s in %s() is not supported yet.\n", |
---|
| 5318 | + i, btf_kind_str[BTF_INFO_KIND(t->info)], tname); |
---|
| 5319 | + return -EINVAL; |
---|
| 5320 | + } |
---|
| 5321 | + return 0; |
---|
| 5322 | +} |
---|
| 5323 | + |
---|
| 5324 | +static void btf_type_show(const struct btf *btf, u32 type_id, void *obj, |
---|
| 5325 | + struct btf_show *show) |
---|
2311 | 5326 | { |
---|
2312 | 5327 | const struct btf_type *t = btf_type_by_id(btf, type_id); |
---|
2313 | 5328 | |
---|
2314 | | - btf_type_ops(t)->seq_show(btf, t, type_id, obj, 0, m); |
---|
| 5329 | + show->btf = btf; |
---|
| 5330 | + memset(&show->state, 0, sizeof(show->state)); |
---|
| 5331 | + memset(&show->obj, 0, sizeof(show->obj)); |
---|
| 5332 | + |
---|
| 5333 | + btf_type_ops(t)->show(btf, t, type_id, obj, 0, show); |
---|
2315 | 5334 | } |
---|
| 5335 | + |
---|
| 5336 | +static void btf_seq_show(struct btf_show *show, const char *fmt, |
---|
| 5337 | + va_list args) |
---|
| 5338 | +{ |
---|
| 5339 | + seq_vprintf((struct seq_file *)show->target, fmt, args); |
---|
| 5340 | +} |
---|
| 5341 | + |
---|
| 5342 | +int btf_type_seq_show_flags(const struct btf *btf, u32 type_id, |
---|
| 5343 | + void *obj, struct seq_file *m, u64 flags) |
---|
| 5344 | +{ |
---|
| 5345 | + struct btf_show sseq; |
---|
| 5346 | + |
---|
| 5347 | + sseq.target = m; |
---|
| 5348 | + sseq.showfn = btf_seq_show; |
---|
| 5349 | + sseq.flags = flags; |
---|
| 5350 | + |
---|
| 5351 | + btf_type_show(btf, type_id, obj, &sseq); |
---|
| 5352 | + |
---|
| 5353 | + return sseq.state.status; |
---|
| 5354 | +} |
---|
| 5355 | + |
---|
| 5356 | +void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj, |
---|
| 5357 | + struct seq_file *m) |
---|
| 5358 | +{ |
---|
| 5359 | + (void) btf_type_seq_show_flags(btf, type_id, obj, m, |
---|
| 5360 | + BTF_SHOW_NONAME | BTF_SHOW_COMPACT | |
---|
| 5361 | + BTF_SHOW_ZERO | BTF_SHOW_UNSAFE); |
---|
| 5362 | +} |
---|
| 5363 | + |
---|
| 5364 | +struct btf_show_snprintf { |
---|
| 5365 | + struct btf_show show; |
---|
| 5366 | + int len_left; /* space left in string */ |
---|
| 5367 | + int len; /* length we would have written */ |
---|
| 5368 | +}; |
---|
| 5369 | + |
---|
| 5370 | +static void btf_snprintf_show(struct btf_show *show, const char *fmt, |
---|
| 5371 | + va_list args) |
---|
| 5372 | +{ |
---|
| 5373 | + struct btf_show_snprintf *ssnprintf = (struct btf_show_snprintf *)show; |
---|
| 5374 | + int len; |
---|
| 5375 | + |
---|
| 5376 | + len = vsnprintf(show->target, ssnprintf->len_left, fmt, args); |
---|
| 5377 | + |
---|
| 5378 | + if (len < 0) { |
---|
| 5379 | + ssnprintf->len_left = 0; |
---|
| 5380 | + ssnprintf->len = len; |
---|
| 5381 | + } else if (len > ssnprintf->len_left) { |
---|
| 5382 | + /* no space, drive on to get length we would have written */ |
---|
| 5383 | + ssnprintf->len_left = 0; |
---|
| 5384 | + ssnprintf->len += len; |
---|
| 5385 | + } else { |
---|
| 5386 | + ssnprintf->len_left -= len; |
---|
| 5387 | + ssnprintf->len += len; |
---|
| 5388 | + show->target += len; |
---|
| 5389 | + } |
---|
| 5390 | +} |
---|
| 5391 | + |
---|
| 5392 | +int btf_type_snprintf_show(const struct btf *btf, u32 type_id, void *obj, |
---|
| 5393 | + char *buf, int len, u64 flags) |
---|
| 5394 | +{ |
---|
| 5395 | + struct btf_show_snprintf ssnprintf; |
---|
| 5396 | + |
---|
| 5397 | + ssnprintf.show.target = buf; |
---|
| 5398 | + ssnprintf.show.flags = flags; |
---|
| 5399 | + ssnprintf.show.showfn = btf_snprintf_show; |
---|
| 5400 | + ssnprintf.len_left = len; |
---|
| 5401 | + ssnprintf.len = 0; |
---|
| 5402 | + |
---|
| 5403 | + btf_type_show(btf, type_id, obj, (struct btf_show *)&ssnprintf); |
---|
| 5404 | + |
---|
| 5405 | + /* If we encontered an error, return it. */ |
---|
| 5406 | + if (ssnprintf.show.state.status) |
---|
| 5407 | + return ssnprintf.show.state.status; |
---|
| 5408 | + |
---|
| 5409 | + /* Otherwise return length we would have written */ |
---|
| 5410 | + return ssnprintf.len; |
---|
| 5411 | +} |
---|
| 5412 | + |
---|
| 5413 | +#ifdef CONFIG_PROC_FS |
---|
| 5414 | +static void bpf_btf_show_fdinfo(struct seq_file *m, struct file *filp) |
---|
| 5415 | +{ |
---|
| 5416 | + const struct btf *btf = filp->private_data; |
---|
| 5417 | + |
---|
| 5418 | + seq_printf(m, "btf_id:\t%u\n", btf->id); |
---|
| 5419 | +} |
---|
| 5420 | +#endif |
---|
2316 | 5421 | |
---|
2317 | 5422 | static int btf_release(struct inode *inode, struct file *filp) |
---|
2318 | 5423 | { |
---|
.. | .. |
---|
2321 | 5426 | } |
---|
2322 | 5427 | |
---|
2323 | 5428 | const struct file_operations btf_fops = { |
---|
| 5429 | +#ifdef CONFIG_PROC_FS |
---|
| 5430 | + .show_fdinfo = bpf_btf_show_fdinfo, |
---|
| 5431 | +#endif |
---|
2324 | 5432 | .release = btf_release, |
---|
2325 | 5433 | }; |
---|
2326 | 5434 | |
---|
.. | .. |
---|
2439 | 5547 | { |
---|
2440 | 5548 | return btf->id; |
---|
2441 | 5549 | } |
---|
| 5550 | + |
---|
| 5551 | +static int btf_id_cmp_func(const void *a, const void *b) |
---|
| 5552 | +{ |
---|
| 5553 | + const int *pa = a, *pb = b; |
---|
| 5554 | + |
---|
| 5555 | + return *pa - *pb; |
---|
| 5556 | +} |
---|
| 5557 | + |
---|
| 5558 | +bool btf_id_set_contains(const struct btf_id_set *set, u32 id) |
---|
| 5559 | +{ |
---|
| 5560 | + return bsearch(&id, set->ids, set->cnt, sizeof(u32), btf_id_cmp_func) != NULL; |
---|
| 5561 | +} |
---|