hc
2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c
kernel/kernel/bpf/btf.c
....@@ -2,6 +2,8 @@
22 /* Copyright (c) 2018 Facebook */
33
44 #include <uapi/linux/btf.h>
5
+#include <uapi/linux/bpf.h>
6
+#include <uapi/linux/bpf_perf_event.h>
57 #include <uapi/linux/types.h>
68 #include <linux/seq_file.h>
79 #include <linux/compiler.h>
....@@ -16,6 +18,12 @@
1618 #include <linux/sort.h>
1719 #include <linux/bpf_verifier.h>
1820 #include <linux/btf.h>
21
+#include <linux/btf_ids.h>
22
+#include <linux/skmsg.h>
23
+#include <linux/perf_event.h>
24
+#include <linux/bsearch.h>
25
+#include <linux/btf_ids.h>
26
+#include <net/sock.h>
1927
2028 /* BTF (BPF Type Format) is the meta data format which describes
2129 * the data types of BPF program/map. Hence, it basically focus
....@@ -157,14 +165,14 @@
157165 *
158166 */
159167
160
-#define BITS_PER_U64 (sizeof(u64) * BITS_PER_BYTE)
168
+#define BITS_PER_U128 (sizeof(u64) * BITS_PER_BYTE * 2)
161169 #define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1)
162170 #define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK)
163171 #define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3)
164172 #define BITS_ROUNDUP_BYTES(bits) \
165173 (BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits))
166174
167
-#define BTF_INFO_MASK 0x0f00ffff
175
+#define BTF_INFO_MASK 0x8f00ffff
168176 #define BTF_INT_MASK 0x0fffffff
169177 #define BTF_TYPE_ID_VALID(type_id) ((type_id) <= BTF_MAX_TYPE)
170178 #define BTF_STR_OFFSET_VALID(name_off) ((name_off) <= BTF_MAX_NAME_OFFSET)
....@@ -175,18 +183,18 @@
175183 */
176184 #define BTF_MAX_SIZE (16 * 1024 * 1024)
177185
178
-#define for_each_member(i, struct_type, member) \
179
- for (i = 0, member = btf_type_member(struct_type); \
180
- i < btf_type_vlen(struct_type); \
181
- i++, member++)
182
-
183186 #define for_each_member_from(i, from, struct_type, member) \
184187 for (i = from, member = btf_type_member(struct_type) + from; \
185188 i < btf_type_vlen(struct_type); \
186189 i++, member++)
187190
188
-static DEFINE_IDR(btf_idr);
189
-static DEFINE_SPINLOCK(btf_idr_lock);
191
+#define for_each_vsi_from(i, from, struct_type, member) \
192
+ for (i = from, member = btf_type_var_secinfo(struct_type) + from; \
193
+ i < btf_type_vlen(struct_type); \
194
+ i++, member++)
195
+
196
+DEFINE_IDR(btf_idr);
197
+DEFINE_SPINLOCK(btf_idr_lock);
190198
191199 struct btf {
192200 void *data;
....@@ -260,6 +268,100 @@
260268 [BTF_KIND_VOLATILE] = "VOLATILE",
261269 [BTF_KIND_CONST] = "CONST",
262270 [BTF_KIND_RESTRICT] = "RESTRICT",
271
+ [BTF_KIND_FUNC] = "FUNC",
272
+ [BTF_KIND_FUNC_PROTO] = "FUNC_PROTO",
273
+ [BTF_KIND_VAR] = "VAR",
274
+ [BTF_KIND_DATASEC] = "DATASEC",
275
+};
276
+
277
+static const char *btf_type_str(const struct btf_type *t)
278
+{
279
+ return btf_kind_str[BTF_INFO_KIND(t->info)];
280
+}
281
+
282
+/* Chunk size we use in safe copy of data to be shown. */
283
+#define BTF_SHOW_OBJ_SAFE_SIZE 32
284
+
285
+/*
286
+ * This is the maximum size of a base type value (equivalent to a
287
+ * 128-bit int); if we are at the end of our safe buffer and have
288
+ * less than 16 bytes space we can't be assured of being able
289
+ * to copy the next type safely, so in such cases we will initiate
290
+ * a new copy.
291
+ */
292
+#define BTF_SHOW_OBJ_BASE_TYPE_SIZE 16
293
+
294
+/* Type name size */
295
+#define BTF_SHOW_NAME_SIZE 80
296
+
297
+/*
298
+ * Common data to all BTF show operations. Private show functions can add
299
+ * their own data to a structure containing a struct btf_show and consult it
300
+ * in the show callback. See btf_type_show() below.
301
+ *
302
+ * One challenge with showing nested data is we want to skip 0-valued
303
+ * data, but in order to figure out whether a nested object is all zeros
304
+ * we need to walk through it. As a result, we need to make two passes
305
+ * when handling structs, unions and arrays; the first path simply looks
306
+ * for nonzero data, while the second actually does the display. The first
307
+ * pass is signalled by show->state.depth_check being set, and if we
308
+ * encounter a non-zero value we set show->state.depth_to_show to
309
+ * the depth at which we encountered it. When we have completed the
310
+ * first pass, we will know if anything needs to be displayed if
311
+ * depth_to_show > depth. See btf_[struct,array]_show() for the
312
+ * implementation of this.
313
+ *
314
+ * Another problem is we want to ensure the data for display is safe to
315
+ * access. To support this, the anonymous "struct {} obj" tracks the data
316
+ * object and our safe copy of it. We copy portions of the data needed
317
+ * to the object "copy" buffer, but because its size is limited to
318
+ * BTF_SHOW_OBJ_COPY_LEN bytes, multiple copies may be required as we
319
+ * traverse larger objects for display.
320
+ *
321
+ * The various data type show functions all start with a call to
322
+ * btf_show_start_type() which returns a pointer to the safe copy
323
+ * of the data needed (or if BTF_SHOW_UNSAFE is specified, to the
324
+ * raw data itself). btf_show_obj_safe() is responsible for
325
+ * using copy_from_kernel_nofault() to update the safe data if necessary
326
+ * as we traverse the object's data. skbuff-like semantics are
327
+ * used:
328
+ *
329
+ * - obj.head points to the start of the toplevel object for display
330
+ * - obj.size is the size of the toplevel object
331
+ * - obj.data points to the current point in the original data at
332
+ * which our safe data starts. obj.data will advance as we copy
333
+ * portions of the data.
334
+ *
335
+ * In most cases a single copy will suffice, but larger data structures
336
+ * such as "struct task_struct" will require many copies. The logic in
337
+ * btf_show_obj_safe() handles the logic that determines if a new
338
+ * copy_from_kernel_nofault() is needed.
339
+ */
340
+struct btf_show {
341
+ u64 flags;
342
+ void *target; /* target of show operation (seq file, buffer) */
343
+ void (*showfn)(struct btf_show *show, const char *fmt, va_list args);
344
+ const struct btf *btf;
345
+ /* below are used during iteration */
346
+ struct {
347
+ u8 depth;
348
+ u8 depth_to_show;
349
+ u8 depth_check;
350
+ u8 array_member:1,
351
+ array_terminated:1;
352
+ u16 array_encoding;
353
+ u32 type_id;
354
+ int status; /* non-zero for error */
355
+ const struct btf_type *type;
356
+ const struct btf_member *member;
357
+ char name[BTF_SHOW_NAME_SIZE]; /* space for member name/type */
358
+ } state;
359
+ struct {
360
+ u32 size;
361
+ void *head;
362
+ void *data;
363
+ u8 safe[BTF_SHOW_OBJ_SAFE_SIZE];
364
+ } obj;
263365 };
264366
265367 struct btf_kind_operations {
....@@ -272,15 +374,22 @@
272374 const struct btf_type *struct_type,
273375 const struct btf_member *member,
274376 const struct btf_type *member_type);
377
+ int (*check_kflag_member)(struct btf_verifier_env *env,
378
+ const struct btf_type *struct_type,
379
+ const struct btf_member *member,
380
+ const struct btf_type *member_type);
275381 void (*log_details)(struct btf_verifier_env *env,
276382 const struct btf_type *t);
277
- void (*seq_show)(const struct btf *btf, const struct btf_type *t,
383
+ void (*show)(const struct btf *btf, const struct btf_type *t,
278384 u32 type_id, void *data, u8 bits_offsets,
279
- struct seq_file *m);
385
+ struct btf_show *show);
280386 };
281387
282388 static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS];
283389 static struct btf_type btf_void;
390
+
391
+static int btf_resolve(struct btf_verifier_env *env,
392
+ const struct btf_type *t, u32 type_id);
284393
285394 static bool btf_type_is_modifier(const struct btf_type *t)
286395 {
....@@ -305,27 +414,30 @@
305414 return false;
306415 }
307416
308
-static bool btf_type_is_void(const struct btf_type *t)
417
+bool btf_type_is_void(const struct btf_type *t)
309418 {
310
- /* void => no type and size info.
311
- * Hence, FWD is also treated as void.
312
- */
313
- return t == &btf_void || BTF_INFO_KIND(t->info) == BTF_KIND_FWD;
419
+ return t == &btf_void;
314420 }
315421
316
-static bool btf_type_is_void_or_null(const struct btf_type *t)
422
+static bool btf_type_is_fwd(const struct btf_type *t)
317423 {
318
- return !t || btf_type_is_void(t);
424
+ return BTF_INFO_KIND(t->info) == BTF_KIND_FWD;
319425 }
320426
321
-/* union is only a special case of struct:
322
- * all its offsetof(member) == 0
323
- */
324
-static bool btf_type_is_struct(const struct btf_type *t)
427
+static bool btf_type_nosize(const struct btf_type *t)
325428 {
326
- u8 kind = BTF_INFO_KIND(t->info);
429
+ return btf_type_is_void(t) || btf_type_is_fwd(t) ||
430
+ btf_type_is_func(t) || btf_type_is_func_proto(t);
431
+}
327432
328
- return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
433
+static bool btf_type_nosize_or_null(const struct btf_type *t)
434
+{
435
+ return !t || btf_type_nosize(t);
436
+}
437
+
438
+static bool __btf_type_is_struct(const struct btf_type *t)
439
+{
440
+ return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT;
329441 }
330442
331443 static bool btf_type_is_array(const struct btf_type *t)
....@@ -333,14 +445,77 @@
333445 return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY;
334446 }
335447
336
-static bool btf_type_is_ptr(const struct btf_type *t)
448
+static bool btf_type_is_datasec(const struct btf_type *t)
337449 {
338
- return BTF_INFO_KIND(t->info) == BTF_KIND_PTR;
450
+ return BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC;
339451 }
340452
341
-static bool btf_type_is_int(const struct btf_type *t)
453
+s32 btf_find_by_name_kind(const struct btf *btf, const char *name, u8 kind)
342454 {
343
- return BTF_INFO_KIND(t->info) == BTF_KIND_INT;
455
+ const struct btf_type *t;
456
+ const char *tname;
457
+ u32 i;
458
+
459
+ for (i = 1; i <= btf->nr_types; i++) {
460
+ t = btf->types[i];
461
+ if (BTF_INFO_KIND(t->info) != kind)
462
+ continue;
463
+
464
+ tname = btf_name_by_offset(btf, t->name_off);
465
+ if (!strcmp(tname, name))
466
+ return i;
467
+ }
468
+
469
+ return -ENOENT;
470
+}
471
+
472
+const struct btf_type *btf_type_skip_modifiers(const struct btf *btf,
473
+ u32 id, u32 *res_id)
474
+{
475
+ const struct btf_type *t = btf_type_by_id(btf, id);
476
+
477
+ while (btf_type_is_modifier(t)) {
478
+ id = t->type;
479
+ t = btf_type_by_id(btf, t->type);
480
+ }
481
+
482
+ if (res_id)
483
+ *res_id = id;
484
+
485
+ return t;
486
+}
487
+
488
+const struct btf_type *btf_type_resolve_ptr(const struct btf *btf,
489
+ u32 id, u32 *res_id)
490
+{
491
+ const struct btf_type *t;
492
+
493
+ t = btf_type_skip_modifiers(btf, id, NULL);
494
+ if (!btf_type_is_ptr(t))
495
+ return NULL;
496
+
497
+ return btf_type_skip_modifiers(btf, t->type, res_id);
498
+}
499
+
500
+const struct btf_type *btf_type_resolve_func_ptr(const struct btf *btf,
501
+ u32 id, u32 *res_id)
502
+{
503
+ const struct btf_type *ptype;
504
+
505
+ ptype = btf_type_resolve_ptr(btf, id, res_id);
506
+ if (ptype && btf_type_is_func_proto(ptype))
507
+ return ptype;
508
+
509
+ return NULL;
510
+}
511
+
512
+/* Types that act only as a source, not sink or intermediate
513
+ * type when resolving.
514
+ */
515
+static bool btf_type_is_resolve_source_only(const struct btf_type *t)
516
+{
517
+ return btf_type_is_var(t) ||
518
+ btf_type_is_datasec(t);
344519 }
345520
346521 /* What types need to be resolved?
....@@ -349,7 +524,11 @@
349524 *
350525 * btf_type_is_struct() because its member refers to
351526 * another type (through member->type).
352
-
527
+ *
528
+ * btf_type_is_var() because the variable refers to
529
+ * another type. btf_type_is_datasec() holds multiple
530
+ * btf_type_is_var() types that need resolving.
531
+ *
353532 * btf_type_is_array() because its element (array->type)
354533 * refers to another type. Array can be thought of a
355534 * special case of struct while array just has the same
....@@ -358,9 +537,11 @@
358537 static bool btf_type_needs_resolve(const struct btf_type *t)
359538 {
360539 return btf_type_is_modifier(t) ||
361
- btf_type_is_ptr(t) ||
362
- btf_type_is_struct(t) ||
363
- btf_type_is_array(t);
540
+ btf_type_is_ptr(t) ||
541
+ btf_type_is_struct(t) ||
542
+ btf_type_is_array(t) ||
543
+ btf_type_is_var(t) ||
544
+ btf_type_is_datasec(t);
364545 }
365546
366547 /* t->size can be used */
....@@ -371,6 +552,7 @@
371552 case BTF_KIND_STRUCT:
372553 case BTF_KIND_UNION:
373554 case BTF_KIND_ENUM:
555
+ case BTF_KIND_DATASEC:
374556 return true;
375557 }
376558
....@@ -391,11 +573,6 @@
391573 return "UNKN";
392574 }
393575
394
-static u16 btf_type_vlen(const struct btf_type *t)
395
-{
396
- return BTF_INFO_VLEN(t->info);
397
-}
398
-
399576 static u32 btf_type_int(const struct btf_type *t)
400577 {
401578 return *(u32 *)(t + 1);
....@@ -406,14 +583,14 @@
406583 return (const struct btf_array *)(t + 1);
407584 }
408585
409
-static const struct btf_member *btf_type_member(const struct btf_type *t)
410
-{
411
- return (const struct btf_member *)(t + 1);
412
-}
413
-
414586 static const struct btf_enum *btf_type_enum(const struct btf_type *t)
415587 {
416588 return (const struct btf_enum *)(t + 1);
589
+}
590
+
591
+static const struct btf_var *btf_type_var(const struct btf_type *t)
592
+{
593
+ return (const struct btf_var *)(t + 1);
417594 }
418595
419596 static const struct btf_kind_operations *btf_type_ops(const struct btf_type *t)
....@@ -427,23 +604,30 @@
427604 offset < btf->hdr.str_len;
428605 }
429606
430
-/* Only C-style identifier is permitted. This can be relaxed if
431
- * necessary.
432
- */
433
-static bool btf_name_valid_identifier(const struct btf *btf, u32 offset)
607
+static bool __btf_name_char_ok(char c, bool first)
608
+{
609
+ if ((first ? !isalpha(c) :
610
+ !isalnum(c)) &&
611
+ c != '_' &&
612
+ c != '.')
613
+ return false;
614
+ return true;
615
+}
616
+
617
+static bool __btf_name_valid(const struct btf *btf, u32 offset)
434618 {
435619 /* offset must be valid */
436620 const char *src = &btf->strings[offset];
437621 const char *src_limit;
438622
439
- if (!isalpha(*src) && *src != '_')
623
+ if (!__btf_name_char_ok(*src, true))
440624 return false;
441625
442626 /* set a limit on identifier length */
443627 src_limit = src + KSYM_NAME_LEN;
444628 src++;
445629 while (*src && src < src_limit) {
446
- if (!isalnum(*src) && *src != '_')
630
+ if (!__btf_name_char_ok(*src, false))
447631 return false;
448632 src++;
449633 }
....@@ -451,7 +635,17 @@
451635 return !*src;
452636 }
453637
454
-static const char *btf_name_by_offset(const struct btf *btf, u32 offset)
638
+static bool btf_name_valid_identifier(const struct btf *btf, u32 offset)
639
+{
640
+ return __btf_name_valid(btf, offset);
641
+}
642
+
643
+static bool btf_name_valid_section(const struct btf *btf, u32 offset)
644
+{
645
+ return __btf_name_valid(btf, offset);
646
+}
647
+
648
+static const char *__btf_name_by_offset(const struct btf *btf, u32 offset)
455649 {
456650 if (!offset)
457651 return "(anon)";
....@@ -461,7 +655,15 @@
461655 return "(invalid-name-offset)";
462656 }
463657
464
-static const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id)
658
+const char *btf_name_by_offset(const struct btf *btf, u32 offset)
659
+{
660
+ if (offset < btf->hdr.str_len)
661
+ return &btf->strings[offset];
662
+
663
+ return NULL;
664
+}
665
+
666
+const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id)
465667 {
466668 if (type_id > btf->nr_types)
467669 return NULL;
....@@ -471,7 +673,7 @@
471673
472674 /*
473675 * Regular int is not a bit field and it must be either
474
- * u8/u16/u32/u64.
676
+ * u8/u16/u32/u64 or __int128.
475677 */
476678 static bool btf_type_int_is_regular(const struct btf_type *t)
477679 {
....@@ -484,11 +686,535 @@
484686 if (BITS_PER_BYTE_MASKED(nr_bits) ||
485687 BTF_INT_OFFSET(int_data) ||
486688 (nr_bytes != sizeof(u8) && nr_bytes != sizeof(u16) &&
487
- nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64))) {
689
+ nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64) &&
690
+ nr_bytes != (2 * sizeof(u64)))) {
488691 return false;
489692 }
490693
491694 return true;
695
+}
696
+
697
+/*
698
+ * Check that given struct member is a regular int with expected
699
+ * offset and size.
700
+ */
701
+bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s,
702
+ const struct btf_member *m,
703
+ u32 expected_offset, u32 expected_size)
704
+{
705
+ const struct btf_type *t;
706
+ u32 id, int_data;
707
+ u8 nr_bits;
708
+
709
+ id = m->type;
710
+ t = btf_type_id_size(btf, &id, NULL);
711
+ if (!t || !btf_type_is_int(t))
712
+ return false;
713
+
714
+ int_data = btf_type_int(t);
715
+ nr_bits = BTF_INT_BITS(int_data);
716
+ if (btf_type_kflag(s)) {
717
+ u32 bitfield_size = BTF_MEMBER_BITFIELD_SIZE(m->offset);
718
+ u32 bit_offset = BTF_MEMBER_BIT_OFFSET(m->offset);
719
+
720
+ /* if kflag set, int should be a regular int and
721
+ * bit offset should be at byte boundary.
722
+ */
723
+ return !bitfield_size &&
724
+ BITS_ROUNDUP_BYTES(bit_offset) == expected_offset &&
725
+ BITS_ROUNDUP_BYTES(nr_bits) == expected_size;
726
+ }
727
+
728
+ if (BTF_INT_OFFSET(int_data) ||
729
+ BITS_PER_BYTE_MASKED(m->offset) ||
730
+ BITS_ROUNDUP_BYTES(m->offset) != expected_offset ||
731
+ BITS_PER_BYTE_MASKED(nr_bits) ||
732
+ BITS_ROUNDUP_BYTES(nr_bits) != expected_size)
733
+ return false;
734
+
735
+ return true;
736
+}
737
+
738
+/* Similar to btf_type_skip_modifiers() but does not skip typedefs. */
739
+static const struct btf_type *btf_type_skip_qualifiers(const struct btf *btf,
740
+ u32 id)
741
+{
742
+ const struct btf_type *t = btf_type_by_id(btf, id);
743
+
744
+ while (btf_type_is_modifier(t) &&
745
+ BTF_INFO_KIND(t->info) != BTF_KIND_TYPEDEF) {
746
+ id = t->type;
747
+ t = btf_type_by_id(btf, t->type);
748
+ }
749
+
750
+ return t;
751
+}
752
+
753
+#define BTF_SHOW_MAX_ITER 10
754
+
755
+#define BTF_KIND_BIT(kind) (1ULL << kind)
756
+
757
+/*
758
+ * Populate show->state.name with type name information.
759
+ * Format of type name is
760
+ *
761
+ * [.member_name = ] (type_name)
762
+ */
763
+static const char *btf_show_name(struct btf_show *show)
764
+{
765
+ /* BTF_MAX_ITER array suffixes "[]" */
766
+ const char *array_suffixes = "[][][][][][][][][][]";
767
+ const char *array_suffix = &array_suffixes[strlen(array_suffixes)];
768
+ /* BTF_MAX_ITER pointer suffixes "*" */
769
+ const char *ptr_suffixes = "**********";
770
+ const char *ptr_suffix = &ptr_suffixes[strlen(ptr_suffixes)];
771
+ const char *name = NULL, *prefix = "", *parens = "";
772
+ const struct btf_member *m = show->state.member;
773
+ const struct btf_type *t = show->state.type;
774
+ const struct btf_array *array;
775
+ u32 id = show->state.type_id;
776
+ const char *member = NULL;
777
+ bool show_member = false;
778
+ u64 kinds = 0;
779
+ int i;
780
+
781
+ show->state.name[0] = '\0';
782
+
783
+ /*
784
+ * Don't show type name if we're showing an array member;
785
+ * in that case we show the array type so don't need to repeat
786
+ * ourselves for each member.
787
+ */
788
+ if (show->state.array_member)
789
+ return "";
790
+
791
+ /* Retrieve member name, if any. */
792
+ if (m) {
793
+ member = btf_name_by_offset(show->btf, m->name_off);
794
+ show_member = strlen(member) > 0;
795
+ id = m->type;
796
+ }
797
+
798
+ /*
799
+ * Start with type_id, as we have resolved the struct btf_type *
800
+ * via btf_modifier_show() past the parent typedef to the child
801
+ * struct, int etc it is defined as. In such cases, the type_id
802
+ * still represents the starting type while the struct btf_type *
803
+ * in our show->state points at the resolved type of the typedef.
804
+ */
805
+ t = btf_type_by_id(show->btf, id);
806
+ if (!t)
807
+ return "";
808
+
809
+ /*
810
+ * The goal here is to build up the right number of pointer and
811
+ * array suffixes while ensuring the type name for a typedef
812
+ * is represented. Along the way we accumulate a list of
813
+ * BTF kinds we have encountered, since these will inform later
814
+ * display; for example, pointer types will not require an
815
+ * opening "{" for struct, we will just display the pointer value.
816
+ *
817
+ * We also want to accumulate the right number of pointer or array
818
+ * indices in the format string while iterating until we get to
819
+ * the typedef/pointee/array member target type.
820
+ *
821
+ * We start by pointing at the end of pointer and array suffix
822
+ * strings; as we accumulate pointers and arrays we move the pointer
823
+ * or array string backwards so it will show the expected number of
824
+ * '*' or '[]' for the type. BTF_SHOW_MAX_ITER of nesting of pointers
825
+ * and/or arrays and typedefs are supported as a precaution.
826
+ *
827
+ * We also want to get typedef name while proceeding to resolve
828
+ * type it points to so that we can add parentheses if it is a
829
+ * "typedef struct" etc.
830
+ */
831
+ for (i = 0; i < BTF_SHOW_MAX_ITER; i++) {
832
+
833
+ switch (BTF_INFO_KIND(t->info)) {
834
+ case BTF_KIND_TYPEDEF:
835
+ if (!name)
836
+ name = btf_name_by_offset(show->btf,
837
+ t->name_off);
838
+ kinds |= BTF_KIND_BIT(BTF_KIND_TYPEDEF);
839
+ id = t->type;
840
+ break;
841
+ case BTF_KIND_ARRAY:
842
+ kinds |= BTF_KIND_BIT(BTF_KIND_ARRAY);
843
+ parens = "[";
844
+ if (!t)
845
+ return "";
846
+ array = btf_type_array(t);
847
+ if (array_suffix > array_suffixes)
848
+ array_suffix -= 2;
849
+ id = array->type;
850
+ break;
851
+ case BTF_KIND_PTR:
852
+ kinds |= BTF_KIND_BIT(BTF_KIND_PTR);
853
+ if (ptr_suffix > ptr_suffixes)
854
+ ptr_suffix -= 1;
855
+ id = t->type;
856
+ break;
857
+ default:
858
+ id = 0;
859
+ break;
860
+ }
861
+ if (!id)
862
+ break;
863
+ t = btf_type_skip_qualifiers(show->btf, id);
864
+ }
865
+ /* We may not be able to represent this type; bail to be safe */
866
+ if (i == BTF_SHOW_MAX_ITER)
867
+ return "";
868
+
869
+ if (!name)
870
+ name = btf_name_by_offset(show->btf, t->name_off);
871
+
872
+ switch (BTF_INFO_KIND(t->info)) {
873
+ case BTF_KIND_STRUCT:
874
+ case BTF_KIND_UNION:
875
+ prefix = BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT ?
876
+ "struct" : "union";
877
+ /* if it's an array of struct/union, parens is already set */
878
+ if (!(kinds & (BTF_KIND_BIT(BTF_KIND_ARRAY))))
879
+ parens = "{";
880
+ break;
881
+ case BTF_KIND_ENUM:
882
+ prefix = "enum";
883
+ break;
884
+ default:
885
+ break;
886
+ }
887
+
888
+ /* pointer does not require parens */
889
+ if (kinds & BTF_KIND_BIT(BTF_KIND_PTR))
890
+ parens = "";
891
+ /* typedef does not require struct/union/enum prefix */
892
+ if (kinds & BTF_KIND_BIT(BTF_KIND_TYPEDEF))
893
+ prefix = "";
894
+
895
+ if (!name)
896
+ name = "";
897
+
898
+ /* Even if we don't want type name info, we want parentheses etc */
899
+ if (show->flags & BTF_SHOW_NONAME)
900
+ snprintf(show->state.name, sizeof(show->state.name), "%s",
901
+ parens);
902
+ else
903
+ snprintf(show->state.name, sizeof(show->state.name),
904
+ "%s%s%s(%s%s%s%s%s%s)%s",
905
+ /* first 3 strings comprise ".member = " */
906
+ show_member ? "." : "",
907
+ show_member ? member : "",
908
+ show_member ? " = " : "",
909
+ /* ...next is our prefix (struct, enum, etc) */
910
+ prefix,
911
+ strlen(prefix) > 0 && strlen(name) > 0 ? " " : "",
912
+ /* ...this is the type name itself */
913
+ name,
914
+ /* ...suffixed by the appropriate '*', '[]' suffixes */
915
+ strlen(ptr_suffix) > 0 ? " " : "", ptr_suffix,
916
+ array_suffix, parens);
917
+
918
+ return show->state.name;
919
+}
920
+
921
+static const char *__btf_show_indent(struct btf_show *show)
922
+{
923
+ const char *indents = " ";
924
+ const char *indent = &indents[strlen(indents)];
925
+
926
+ if ((indent - show->state.depth) >= indents)
927
+ return indent - show->state.depth;
928
+ return indents;
929
+}
930
+
931
+static const char *btf_show_indent(struct btf_show *show)
932
+{
933
+ return show->flags & BTF_SHOW_COMPACT ? "" : __btf_show_indent(show);
934
+}
935
+
936
+static const char *btf_show_newline(struct btf_show *show)
937
+{
938
+ return show->flags & BTF_SHOW_COMPACT ? "" : "\n";
939
+}
940
+
941
+static const char *btf_show_delim(struct btf_show *show)
942
+{
943
+ if (show->state.depth == 0)
944
+ return "";
945
+
946
+ if ((show->flags & BTF_SHOW_COMPACT) && show->state.type &&
947
+ BTF_INFO_KIND(show->state.type->info) == BTF_KIND_UNION)
948
+ return "|";
949
+
950
+ return ",";
951
+}
952
+
953
+__printf(2, 3) static void btf_show(struct btf_show *show, const char *fmt, ...)
954
+{
955
+ va_list args;
956
+
957
+ if (!show->state.depth_check) {
958
+ va_start(args, fmt);
959
+ show->showfn(show, fmt, args);
960
+ va_end(args);
961
+ }
962
+}
963
+
964
+/* Macros are used here as btf_show_type_value[s]() prepends and appends
965
+ * format specifiers to the format specifier passed in; these do the work of
966
+ * adding indentation, delimiters etc while the caller simply has to specify
967
+ * the type value(s) in the format specifier + value(s).
968
+ */
969
+#define btf_show_type_value(show, fmt, value) \
970
+ do { \
971
+ if ((value) != 0 || (show->flags & BTF_SHOW_ZERO) || \
972
+ show->state.depth == 0) { \
973
+ btf_show(show, "%s%s" fmt "%s%s", \
974
+ btf_show_indent(show), \
975
+ btf_show_name(show), \
976
+ value, btf_show_delim(show), \
977
+ btf_show_newline(show)); \
978
+ if (show->state.depth > show->state.depth_to_show) \
979
+ show->state.depth_to_show = show->state.depth; \
980
+ } \
981
+ } while (0)
982
+
983
+#define btf_show_type_values(show, fmt, ...) \
984
+ do { \
985
+ btf_show(show, "%s%s" fmt "%s%s", btf_show_indent(show), \
986
+ btf_show_name(show), \
987
+ __VA_ARGS__, btf_show_delim(show), \
988
+ btf_show_newline(show)); \
989
+ if (show->state.depth > show->state.depth_to_show) \
990
+ show->state.depth_to_show = show->state.depth; \
991
+ } while (0)
992
+
993
+/* How much is left to copy to safe buffer after @data? */
994
+static int btf_show_obj_size_left(struct btf_show *show, void *data)
995
+{
996
+ return show->obj.head + show->obj.size - data;
997
+}
998
+
999
+/* Is object pointed to by @data of @size already copied to our safe buffer? */
1000
+static bool btf_show_obj_is_safe(struct btf_show *show, void *data, int size)
1001
+{
1002
+ return data >= show->obj.data &&
1003
+ (data + size) < (show->obj.data + BTF_SHOW_OBJ_SAFE_SIZE);
1004
+}
1005
+
1006
+/*
1007
+ * If object pointed to by @data of @size falls within our safe buffer, return
1008
+ * the equivalent pointer to the same safe data. Assumes
1009
+ * copy_from_kernel_nofault() has already happened and our safe buffer is
1010
+ * populated.
1011
+ */
1012
+static void *__btf_show_obj_safe(struct btf_show *show, void *data, int size)
1013
+{
1014
+ if (btf_show_obj_is_safe(show, data, size))
1015
+ return show->obj.safe + (data - show->obj.data);
1016
+ return NULL;
1017
+}
1018
+
1019
+/*
1020
+ * Return a safe-to-access version of data pointed to by @data.
1021
+ * We do this by copying the relevant amount of information
1022
+ * to the struct btf_show obj.safe buffer using copy_from_kernel_nofault().
1023
+ *
1024
+ * If BTF_SHOW_UNSAFE is specified, just return data as-is; no
1025
+ * safe copy is needed.
1026
+ *
1027
+ * Otherwise we need to determine if we have the required amount
1028
+ * of data (determined by the @data pointer and the size of the
1029
+ * largest base type we can encounter (represented by
1030
+ * BTF_SHOW_OBJ_BASE_TYPE_SIZE). Having that much data ensures
1031
+ * that we will be able to print some of the current object,
1032
+ * and if more is needed a copy will be triggered.
1033
+ * Some objects such as structs will not fit into the buffer;
1034
+ * in such cases additional copies when we iterate over their
1035
+ * members may be needed.
1036
+ *
1037
+ * btf_show_obj_safe() is used to return a safe buffer for
1038
+ * btf_show_start_type(); this ensures that as we recurse into
1039
+ * nested types we always have safe data for the given type.
1040
+ * This approach is somewhat wasteful; it's possible for example
1041
+ * that when iterating over a large union we'll end up copying the
1042
+ * same data repeatedly, but the goal is safety not performance.
1043
+ * We use stack data as opposed to per-CPU buffers because the
1044
+ * iteration over a type can take some time, and preemption handling
1045
+ * would greatly complicate use of the safe buffer.
1046
+ */
1047
+static void *btf_show_obj_safe(struct btf_show *show,
1048
+ const struct btf_type *t,
1049
+ void *data)
1050
+{
1051
+ const struct btf_type *rt;
1052
+ int size_left, size;
1053
+ void *safe = NULL;
1054
+
1055
+ if (show->flags & BTF_SHOW_UNSAFE)
1056
+ return data;
1057
+
1058
+ rt = btf_resolve_size(show->btf, t, &size);
1059
+ if (IS_ERR(rt)) {
1060
+ show->state.status = PTR_ERR(rt);
1061
+ return NULL;
1062
+ }
1063
+
1064
+ /*
1065
+ * Is this toplevel object? If so, set total object size and
1066
+ * initialize pointers. Otherwise check if we still fall within
1067
+ * our safe object data.
1068
+ */
1069
+ if (show->state.depth == 0) {
1070
+ show->obj.size = size;
1071
+ show->obj.head = data;
1072
+ } else {
1073
+ /*
1074
+ * If the size of the current object is > our remaining
1075
+ * safe buffer we _may_ need to do a new copy. However
1076
+ * consider the case of a nested struct; it's size pushes
1077
+ * us over the safe buffer limit, but showing any individual
1078
+ * struct members does not. In such cases, we don't need
1079
+ * to initiate a fresh copy yet; however we definitely need
1080
+ * at least BTF_SHOW_OBJ_BASE_TYPE_SIZE bytes left
1081
+ * in our buffer, regardless of the current object size.
1082
+ * The logic here is that as we resolve types we will
1083
+ * hit a base type at some point, and we need to be sure
1084
+ * the next chunk of data is safely available to display
1085
+ * that type info safely. We cannot rely on the size of
1086
+ * the current object here because it may be much larger
1087
+ * than our current buffer (e.g. task_struct is 8k).
1088
+ * All we want to do here is ensure that we can print the
1089
+ * next basic type, which we can if either
1090
+ * - the current type size is within the safe buffer; or
1091
+ * - at least BTF_SHOW_OBJ_BASE_TYPE_SIZE bytes are left in
1092
+ * the safe buffer.
1093
+ */
1094
+ safe = __btf_show_obj_safe(show, data,
1095
+ min(size,
1096
+ BTF_SHOW_OBJ_BASE_TYPE_SIZE));
1097
+ }
1098
+
1099
+ /*
1100
+ * We need a new copy to our safe object, either because we haven't
1101
+ * yet copied and are intializing safe data, or because the data
1102
+ * we want falls outside the boundaries of the safe object.
1103
+ */
1104
+ if (!safe) {
1105
+ size_left = btf_show_obj_size_left(show, data);
1106
+ if (size_left > BTF_SHOW_OBJ_SAFE_SIZE)
1107
+ size_left = BTF_SHOW_OBJ_SAFE_SIZE;
1108
+ show->state.status = copy_from_kernel_nofault(show->obj.safe,
1109
+ data, size_left);
1110
+ if (!show->state.status) {
1111
+ show->obj.data = data;
1112
+ safe = show->obj.safe;
1113
+ }
1114
+ }
1115
+
1116
+ return safe;
1117
+}
1118
+
1119
+/*
1120
+ * Set the type we are starting to show and return a safe data pointer
1121
+ * to be used for showing the associated data.
1122
+ */
1123
+static void *btf_show_start_type(struct btf_show *show,
1124
+ const struct btf_type *t,
1125
+ u32 type_id, void *data)
1126
+{
1127
+ show->state.type = t;
1128
+ show->state.type_id = type_id;
1129
+ show->state.name[0] = '\0';
1130
+
1131
+ return btf_show_obj_safe(show, t, data);
1132
+}
1133
+
1134
+static void btf_show_end_type(struct btf_show *show)
1135
+{
1136
+ show->state.type = NULL;
1137
+ show->state.type_id = 0;
1138
+ show->state.name[0] = '\0';
1139
+}
1140
+
1141
+static void *btf_show_start_aggr_type(struct btf_show *show,
1142
+ const struct btf_type *t,
1143
+ u32 type_id, void *data)
1144
+{
1145
+ void *safe_data = btf_show_start_type(show, t, type_id, data);
1146
+
1147
+ if (!safe_data)
1148
+ return safe_data;
1149
+
1150
+ btf_show(show, "%s%s%s", btf_show_indent(show),
1151
+ btf_show_name(show),
1152
+ btf_show_newline(show));
1153
+ show->state.depth++;
1154
+ return safe_data;
1155
+}
1156
+
1157
+static void btf_show_end_aggr_type(struct btf_show *show,
1158
+ const char *suffix)
1159
+{
1160
+ show->state.depth--;
1161
+ btf_show(show, "%s%s%s%s", btf_show_indent(show), suffix,
1162
+ btf_show_delim(show), btf_show_newline(show));
1163
+ btf_show_end_type(show);
1164
+}
1165
+
1166
+static void btf_show_start_member(struct btf_show *show,
1167
+ const struct btf_member *m)
1168
+{
1169
+ show->state.member = m;
1170
+}
1171
+
1172
+static void btf_show_start_array_member(struct btf_show *show)
1173
+{
1174
+ show->state.array_member = 1;
1175
+ btf_show_start_member(show, NULL);
1176
+}
1177
+
1178
+static void btf_show_end_member(struct btf_show *show)
1179
+{
1180
+ show->state.member = NULL;
1181
+}
1182
+
1183
+static void btf_show_end_array_member(struct btf_show *show)
1184
+{
1185
+ show->state.array_member = 0;
1186
+ btf_show_end_member(show);
1187
+}
1188
+
1189
+static void *btf_show_start_array_type(struct btf_show *show,
1190
+ const struct btf_type *t,
1191
+ u32 type_id,
1192
+ u16 array_encoding,
1193
+ void *data)
1194
+{
1195
+ show->state.array_encoding = array_encoding;
1196
+ show->state.array_terminated = 0;
1197
+ return btf_show_start_aggr_type(show, t, type_id, data);
1198
+}
1199
+
1200
+static void btf_show_end_array_type(struct btf_show *show)
1201
+{
1202
+ show->state.array_encoding = 0;
1203
+ show->state.array_terminated = 0;
1204
+ btf_show_end_aggr_type(show, "]");
1205
+}
1206
+
1207
+static void *btf_show_start_struct_type(struct btf_show *show,
1208
+ const struct btf_type *t,
1209
+ u32 type_id,
1210
+ void *data)
1211
+{
1212
+ return btf_show_start_aggr_type(show, t, type_id, data);
1213
+}
1214
+
1215
+static void btf_show_end_struct_type(struct btf_show *show)
1216
+{
1217
+ btf_show_end_aggr_type(show, "}");
4921218 }
4931219
4941220 __printf(2, 3) static void __btf_verifier_log(struct bpf_verifier_log *log,
....@@ -528,10 +1254,17 @@
5281254 if (!bpf_verifier_log_needed(log))
5291255 return;
5301256
1257
+ /* btf verifier prints all types it is processing via
1258
+ * btf_verifier_log_type(..., fmt = NULL).
1259
+ * Skip those prints for in-kernel BTF verification.
1260
+ */
1261
+ if (log->level == BPF_LOG_KERNEL && !fmt)
1262
+ return;
1263
+
5311264 __btf_verifier_log(log, "[%u] %s %s%s",
5321265 env->log_type_id,
5331266 btf_kind_str[kind],
534
- btf_name_by_offset(btf, t->name_off),
1267
+ __btf_name_by_offset(btf, t->name_off),
5351268 log_details ? " " : "");
5361269
5371270 if (log_details)
....@@ -565,6 +1298,8 @@
5651298 if (!bpf_verifier_log_needed(log))
5661299 return;
5671300
1301
+ if (log->level == BPF_LOG_KERNEL && !fmt)
1302
+ return;
5681303 /* The CHECK_META phase already did a btf dump.
5691304 *
5701305 * If member is logged again, it must hit an error in
....@@ -574,10 +1309,46 @@
5741309 if (env->phase != CHECK_META)
5751310 btf_verifier_log_type(env, struct_type, NULL);
5761311
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);
1312
+ if (btf_type_kflag(struct_type))
1313
+ __btf_verifier_log(log,
1314
+ "\t%s type_id=%u bitfield_size=%u bits_offset=%u",
1315
+ __btf_name_by_offset(btf, member->name_off),
1316
+ member->type,
1317
+ BTF_MEMBER_BITFIELD_SIZE(member->offset),
1318
+ BTF_MEMBER_BIT_OFFSET(member->offset));
1319
+ else
1320
+ __btf_verifier_log(log, "\t%s type_id=%u bits_offset=%u",
1321
+ __btf_name_by_offset(btf, member->name_off),
1322
+ member->type, member->offset);
5801323
1324
+ if (fmt && *fmt) {
1325
+ __btf_verifier_log(log, " ");
1326
+ va_start(args, fmt);
1327
+ bpf_verifier_vlog(log, fmt, args);
1328
+ va_end(args);
1329
+ }
1330
+
1331
+ __btf_verifier_log(log, "\n");
1332
+}
1333
+
1334
+__printf(4, 5)
1335
+static void btf_verifier_log_vsi(struct btf_verifier_env *env,
1336
+ const struct btf_type *datasec_type,
1337
+ const struct btf_var_secinfo *vsi,
1338
+ const char *fmt, ...)
1339
+{
1340
+ struct bpf_verifier_log *log = &env->log;
1341
+ va_list args;
1342
+
1343
+ if (!bpf_verifier_log_needed(log))
1344
+ return;
1345
+ if (log->level == BPF_LOG_KERNEL && !fmt)
1346
+ return;
1347
+ if (env->phase != CHECK_META)
1348
+ btf_verifier_log_type(env, datasec_type, NULL);
1349
+
1350
+ __btf_verifier_log(log, "\t type_id=%u offset=%u size=%u",
1351
+ vsi->type, vsi->offset, vsi->size);
5811352 if (fmt && *fmt) {
5821353 __btf_verifier_log(log, " ");
5831354 va_start(args, fmt);
....@@ -598,6 +1369,8 @@
5981369 if (!bpf_verifier_log_needed(log))
5991370 return;
6001371
1372
+ if (log->level == BPF_LOG_KERNEL)
1373
+ return;
6011374 hdr = &btf->hdr;
6021375 __btf_verifier_log(log, "magic: 0x%x\n", hdr->magic);
6031376 __btf_verifier_log(log, "version: %u\n", hdr->version);
....@@ -765,11 +1538,15 @@
7651538 /* int, enum or void is a sink */
7661539 return !btf_type_needs_resolve(next_type);
7671540 case RESOLVE_PTR:
768
- /* int, enum, void, struct or array is a sink for ptr */
1541
+ /* int, enum, void, struct, array, func or func_proto is a sink
1542
+ * for ptr
1543
+ */
7691544 return !btf_type_is_modifier(next_type) &&
7701545 !btf_type_is_ptr(next_type);
7711546 case RESOLVE_STRUCT_OR_ARRAY:
772
- /* int, enum, void or ptr is a sink for struct and array */
1547
+ /* int, enum, void, ptr, func or func_proto is a sink
1548
+ * for struct and array
1549
+ */
7731550 return !btf_type_is_modifier(next_type) &&
7741551 !btf_type_is_array(next_type) &&
7751552 !btf_type_is_struct(next_type);
....@@ -835,6 +1612,100 @@
8351612 return env->top_stack ? &env->stack[env->top_stack - 1] : NULL;
8361613 }
8371614
1615
+/* Resolve the size of a passed-in "type"
1616
+ *
1617
+ * type: is an array (e.g. u32 array[x][y])
1618
+ * return type: type "u32[x][y]", i.e. BTF_KIND_ARRAY,
1619
+ * *type_size: (x * y * sizeof(u32)). Hence, *type_size always
1620
+ * corresponds to the return type.
1621
+ * *elem_type: u32
1622
+ * *elem_id: id of u32
1623
+ * *total_nelems: (x * y). Hence, individual elem size is
1624
+ * (*type_size / *total_nelems)
1625
+ * *type_id: id of type if it's changed within the function, 0 if not
1626
+ *
1627
+ * type: is not an array (e.g. const struct X)
1628
+ * return type: type "struct X"
1629
+ * *type_size: sizeof(struct X)
1630
+ * *elem_type: same as return type ("struct X")
1631
+ * *elem_id: 0
1632
+ * *total_nelems: 1
1633
+ * *type_id: id of type if it's changed within the function, 0 if not
1634
+ */
1635
+static const struct btf_type *
1636
+__btf_resolve_size(const struct btf *btf, const struct btf_type *type,
1637
+ u32 *type_size, const struct btf_type **elem_type,
1638
+ u32 *elem_id, u32 *total_nelems, u32 *type_id)
1639
+{
1640
+ const struct btf_type *array_type = NULL;
1641
+ const struct btf_array *array = NULL;
1642
+ u32 i, size, nelems = 1, id = 0;
1643
+
1644
+ for (i = 0; i < MAX_RESOLVE_DEPTH; i++) {
1645
+ switch (BTF_INFO_KIND(type->info)) {
1646
+ /* type->size can be used */
1647
+ case BTF_KIND_INT:
1648
+ case BTF_KIND_STRUCT:
1649
+ case BTF_KIND_UNION:
1650
+ case BTF_KIND_ENUM:
1651
+ size = type->size;
1652
+ goto resolved;
1653
+
1654
+ case BTF_KIND_PTR:
1655
+ size = sizeof(void *);
1656
+ goto resolved;
1657
+
1658
+ /* Modifiers */
1659
+ case BTF_KIND_TYPEDEF:
1660
+ case BTF_KIND_VOLATILE:
1661
+ case BTF_KIND_CONST:
1662
+ case BTF_KIND_RESTRICT:
1663
+ id = type->type;
1664
+ type = btf_type_by_id(btf, type->type);
1665
+ break;
1666
+
1667
+ case BTF_KIND_ARRAY:
1668
+ if (!array_type)
1669
+ array_type = type;
1670
+ array = btf_type_array(type);
1671
+ if (nelems && array->nelems > U32_MAX / nelems)
1672
+ return ERR_PTR(-EINVAL);
1673
+ nelems *= array->nelems;
1674
+ type = btf_type_by_id(btf, array->type);
1675
+ break;
1676
+
1677
+ /* type without size */
1678
+ default:
1679
+ return ERR_PTR(-EINVAL);
1680
+ }
1681
+ }
1682
+
1683
+ return ERR_PTR(-EINVAL);
1684
+
1685
+resolved:
1686
+ if (nelems && size > U32_MAX / nelems)
1687
+ return ERR_PTR(-EINVAL);
1688
+
1689
+ *type_size = nelems * size;
1690
+ if (total_nelems)
1691
+ *total_nelems = nelems;
1692
+ if (elem_type)
1693
+ *elem_type = type;
1694
+ if (elem_id)
1695
+ *elem_id = array ? array->type : 0;
1696
+ if (type_id && id)
1697
+ *type_id = id;
1698
+
1699
+ return array_type ? : type;
1700
+}
1701
+
1702
+const struct btf_type *
1703
+btf_resolve_size(const struct btf *btf, const struct btf_type *type,
1704
+ u32 *type_size)
1705
+{
1706
+ return __btf_resolve_size(btf, type, type_size, NULL, NULL, NULL, NULL);
1707
+}
1708
+
8381709 /* The input param "type_id" must point to a needs_resolve type */
8391710 static const struct btf_type *btf_type_id_resolve(const struct btf *btf,
8401711 u32 *type_id)
....@@ -851,7 +1722,7 @@
8511722 u32 size = 0;
8521723
8531724 size_type = btf_type_by_id(btf, size_type_id);
854
- if (btf_type_is_void_or_null(size_type))
1725
+ if (btf_type_nosize_or_null(size_type))
8551726 return NULL;
8561727
8571728 if (btf_type_has_size(size_type)) {
....@@ -861,13 +1732,21 @@
8611732 } else if (btf_type_is_ptr(size_type)) {
8621733 size = sizeof(void *);
8631734 } else {
864
- if (WARN_ON_ONCE(!btf_type_is_modifier(size_type)))
1735
+ if (WARN_ON_ONCE(!btf_type_is_modifier(size_type) &&
1736
+ !btf_type_is_var(size_type)))
8651737 return NULL;
8661738
867
- size = btf->resolved_sizes[size_type_id];
8681739 size_type_id = btf->resolved_ids[size_type_id];
8691740 size_type = btf_type_by_id(btf, size_type_id);
870
- if (btf_type_is_void(size_type))
1741
+ if (btf_type_nosize_or_null(size_type))
1742
+ return NULL;
1743
+ else if (btf_type_has_size(size_type))
1744
+ size = size_type->size;
1745
+ else if (btf_type_is_array(size_type))
1746
+ size = btf->resolved_sizes[size_type_id];
1747
+ else if (btf_type_is_ptr(size_type))
1748
+ size = sizeof(void *);
1749
+ else
8711750 return NULL;
8721751 }
8731752
....@@ -888,6 +1767,38 @@
8881767 return -EINVAL;
8891768 }
8901769
1770
+static int btf_df_check_kflag_member(struct btf_verifier_env *env,
1771
+ const struct btf_type *struct_type,
1772
+ const struct btf_member *member,
1773
+ const struct btf_type *member_type)
1774
+{
1775
+ btf_verifier_log_basic(env, struct_type,
1776
+ "Unsupported check_kflag_member");
1777
+ return -EINVAL;
1778
+}
1779
+
1780
+/* Used for ptr, array and struct/union type members.
1781
+ * int, enum and modifier types have their specific callback functions.
1782
+ */
1783
+static int btf_generic_check_kflag_member(struct btf_verifier_env *env,
1784
+ const struct btf_type *struct_type,
1785
+ const struct btf_member *member,
1786
+ const struct btf_type *member_type)
1787
+{
1788
+ if (BTF_MEMBER_BITFIELD_SIZE(member->offset)) {
1789
+ btf_verifier_log_member(env, struct_type, member,
1790
+ "Invalid member bitfield_size");
1791
+ return -EINVAL;
1792
+ }
1793
+
1794
+ /* bitfield size is 0, so member->offset represents bit offset only.
1795
+ * It is safe to call non kflag check_member variants.
1796
+ */
1797
+ return btf_type_ops(member_type)->check_member(env, struct_type,
1798
+ member,
1799
+ member_type);
1800
+}
1801
+
8911802 static int btf_df_resolve(struct btf_verifier_env *env,
8921803 const struct resolve_vertex *v)
8931804 {
....@@ -895,11 +1806,11 @@
8951806 return -EINVAL;
8961807 }
8971808
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)
1809
+static void btf_df_show(const struct btf *btf, const struct btf_type *t,
1810
+ u32 type_id, void *data, u8 bits_offsets,
1811
+ struct btf_show *show)
9011812 {
902
- seq_printf(m, "<unsupported kind:%u>", BTF_INFO_KIND(t->info));
1813
+ btf_show(show, "<unsupported kind:%u>", BTF_INFO_KIND(t->info));
9031814 }
9041815
9051816 static int btf_int_check_member(struct btf_verifier_env *env,
....@@ -924,9 +1835,65 @@
9241835 nr_copy_bits = BTF_INT_BITS(int_data) +
9251836 BITS_PER_BYTE_MASKED(struct_bits_off);
9261837
927
- if (nr_copy_bits > BITS_PER_U64) {
1838
+ if (nr_copy_bits > BITS_PER_U128) {
9281839 btf_verifier_log_member(env, struct_type, member,
929
- "nr_copy_bits exceeds 64");
1840
+ "nr_copy_bits exceeds 128");
1841
+ return -EINVAL;
1842
+ }
1843
+
1844
+ if (struct_size < bytes_offset ||
1845
+ struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) {
1846
+ btf_verifier_log_member(env, struct_type, member,
1847
+ "Member exceeds struct_size");
1848
+ return -EINVAL;
1849
+ }
1850
+
1851
+ return 0;
1852
+}
1853
+
1854
+static int btf_int_check_kflag_member(struct btf_verifier_env *env,
1855
+ const struct btf_type *struct_type,
1856
+ const struct btf_member *member,
1857
+ const struct btf_type *member_type)
1858
+{
1859
+ u32 struct_bits_off, nr_bits, nr_int_data_bits, bytes_offset;
1860
+ u32 int_data = btf_type_int(member_type);
1861
+ u32 struct_size = struct_type->size;
1862
+ u32 nr_copy_bits;
1863
+
1864
+ /* a regular int type is required for the kflag int member */
1865
+ if (!btf_type_int_is_regular(member_type)) {
1866
+ btf_verifier_log_member(env, struct_type, member,
1867
+ "Invalid member base type");
1868
+ return -EINVAL;
1869
+ }
1870
+
1871
+ /* check sanity of bitfield size */
1872
+ nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset);
1873
+ struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset);
1874
+ nr_int_data_bits = BTF_INT_BITS(int_data);
1875
+ if (!nr_bits) {
1876
+ /* Not a bitfield member, member offset must be at byte
1877
+ * boundary.
1878
+ */
1879
+ if (BITS_PER_BYTE_MASKED(struct_bits_off)) {
1880
+ btf_verifier_log_member(env, struct_type, member,
1881
+ "Invalid member offset");
1882
+ return -EINVAL;
1883
+ }
1884
+
1885
+ nr_bits = nr_int_data_bits;
1886
+ } else if (nr_bits > nr_int_data_bits) {
1887
+ btf_verifier_log_member(env, struct_type, member,
1888
+ "Invalid member bitfield_size");
1889
+ return -EINVAL;
1890
+ }
1891
+
1892
+ bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off);
1893
+ nr_copy_bits = nr_bits + BITS_PER_BYTE_MASKED(struct_bits_off);
1894
+ if (nr_copy_bits > BITS_PER_U128) {
1895
+ btf_verifier_log_member(env, struct_type, member,
1896
+ "nr_copy_bits exceeds 128");
9301897 return -EINVAL;
9311898 }
9321899
....@@ -959,6 +1926,11 @@
9591926 return -EINVAL;
9601927 }
9611928
1929
+ if (btf_type_kflag(t)) {
1930
+ btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
1931
+ return -EINVAL;
1932
+ }
1933
+
9621934 int_data = btf_type_int(t);
9631935 if (int_data & ~BTF_INT_MASK) {
9641936 btf_verifier_log_basic(env, t, "Invalid int_data:%x",
....@@ -968,9 +1940,9 @@
9681940
9691941 nr_bits = BTF_INT_BITS(int_data) + BTF_INT_OFFSET(int_data);
9701942
971
- if (nr_bits > BITS_PER_U64) {
1943
+ if (nr_bits > BITS_PER_U128) {
9721944 btf_verifier_log_type(env, t, "nr_bits exceeds %zu",
973
- BITS_PER_U64);
1945
+ BITS_PER_U128);
9741946 return -EINVAL;
9751947 }
9761948
....@@ -1011,96 +1983,193 @@
10111983 btf_int_encoding_str(BTF_INT_ENCODING(int_data)));
10121984 }
10131985
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)
1986
+static void btf_int128_print(struct btf_show *show, void *data)
1987
+{
1988
+ /* data points to a __int128 number.
1989
+ * Suppose
1990
+ * int128_num = *(__int128 *)data;
1991
+ * The below formulas shows what upper_num and lower_num represents:
1992
+ * upper_num = int128_num >> 64;
1993
+ * lower_num = int128_num & 0xffffffffFFFFFFFFULL;
1994
+ */
1995
+ u64 upper_num, lower_num;
1996
+
1997
+#ifdef __BIG_ENDIAN_BITFIELD
1998
+ upper_num = *(u64 *)data;
1999
+ lower_num = *(u64 *)(data + 8);
2000
+#else
2001
+ upper_num = *(u64 *)(data + 8);
2002
+ lower_num = *(u64 *)data;
2003
+#endif
2004
+ if (upper_num == 0)
2005
+ btf_show_type_value(show, "0x%llx", lower_num);
2006
+ else
2007
+ btf_show_type_values(show, "0x%llx%016llx", upper_num,
2008
+ lower_num);
2009
+}
2010
+
2011
+static void btf_int128_shift(u64 *print_num, u16 left_shift_bits,
2012
+ u16 right_shift_bits)
2013
+{
2014
+ u64 upper_num, lower_num;
2015
+
2016
+#ifdef __BIG_ENDIAN_BITFIELD
2017
+ upper_num = print_num[0];
2018
+ lower_num = print_num[1];
2019
+#else
2020
+ upper_num = print_num[1];
2021
+ lower_num = print_num[0];
2022
+#endif
2023
+
2024
+ /* shake out un-needed bits by shift/or operations */
2025
+ if (left_shift_bits >= 64) {
2026
+ upper_num = lower_num << (left_shift_bits - 64);
2027
+ lower_num = 0;
2028
+ } else {
2029
+ upper_num = (upper_num << left_shift_bits) |
2030
+ (lower_num >> (64 - left_shift_bits));
2031
+ lower_num = lower_num << left_shift_bits;
2032
+ }
2033
+
2034
+ if (right_shift_bits >= 64) {
2035
+ lower_num = upper_num >> (right_shift_bits - 64);
2036
+ upper_num = 0;
2037
+ } else {
2038
+ lower_num = (lower_num >> right_shift_bits) |
2039
+ (upper_num << (64 - right_shift_bits));
2040
+ upper_num = upper_num >> right_shift_bits;
2041
+ }
2042
+
2043
+#ifdef __BIG_ENDIAN_BITFIELD
2044
+ print_num[0] = upper_num;
2045
+ print_num[1] = lower_num;
2046
+#else
2047
+ print_num[0] = lower_num;
2048
+ print_num[1] = upper_num;
2049
+#endif
2050
+}
2051
+
2052
+static void btf_bitfield_show(void *data, u8 bits_offset,
2053
+ u8 nr_bits, struct btf_show *show)
10182054 {
10192055 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;
10232056 u8 nr_copy_bytes;
10242057 u8 nr_copy_bits;
1025
- u64 print_num;
2058
+ u64 print_num[2] = {};
10262059
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);
10342060 nr_copy_bits = nr_bits + bits_offset;
10352061 nr_copy_bytes = BITS_ROUNDUP_BYTES(nr_copy_bits);
10362062
1037
- print_num = 0;
1038
- memcpy(&print_num, data, nr_copy_bytes);
2063
+ memcpy(print_num, data, nr_copy_bytes);
10392064
10402065 #ifdef __BIG_ENDIAN_BITFIELD
10412066 left_shift_bits = bits_offset;
10422067 #else
1043
- left_shift_bits = BITS_PER_U64 - nr_copy_bits;
2068
+ left_shift_bits = BITS_PER_U128 - nr_copy_bits;
10442069 #endif
1045
- right_shift_bits = BITS_PER_U64 - nr_bits;
2070
+ right_shift_bits = BITS_PER_U128 - nr_bits;
10462071
1047
- print_num <<= left_shift_bits;
1048
- print_num >>= right_shift_bits;
1049
-
1050
- seq_printf(m, "0x%llx", print_num);
2072
+ btf_int128_shift(print_num, left_shift_bits, right_shift_bits);
2073
+ btf_int128_print(show, print_num);
10512074 }
10522075
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)
2076
+
2077
+static void btf_int_bits_show(const struct btf *btf,
2078
+ const struct btf_type *t,
2079
+ void *data, u8 bits_offset,
2080
+ struct btf_show *show)
2081
+{
2082
+ u32 int_data = btf_type_int(t);
2083
+ u8 nr_bits = BTF_INT_BITS(int_data);
2084
+ u8 total_bits_offset;
2085
+
2086
+ /*
2087
+ * bits_offset is at most 7.
2088
+ * BTF_INT_OFFSET() cannot exceed 128 bits.
2089
+ */
2090
+ total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data);
2091
+ data += BITS_ROUNDDOWN_BYTES(total_bits_offset);
2092
+ bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset);
2093
+ btf_bitfield_show(data, bits_offset, nr_bits, show);
2094
+}
2095
+
2096
+static void btf_int_show(const struct btf *btf, const struct btf_type *t,
2097
+ u32 type_id, void *data, u8 bits_offset,
2098
+ struct btf_show *show)
10562099 {
10572100 u32 int_data = btf_type_int(t);
10582101 u8 encoding = BTF_INT_ENCODING(int_data);
10592102 bool sign = encoding & BTF_INT_SIGNED;
10602103 u8 nr_bits = BTF_INT_BITS(int_data);
2104
+ void *safe_data;
2105
+
2106
+ safe_data = btf_show_start_type(show, t, type_id, data);
2107
+ if (!safe_data)
2108
+ return;
10612109
10622110 if (bits_offset || BTF_INT_OFFSET(int_data) ||
10632111 BITS_PER_BYTE_MASKED(nr_bits)) {
1064
- btf_int_bits_seq_show(btf, t, data, bits_offset, m);
1065
- return;
2112
+ btf_int_bits_show(btf, t, safe_data, bits_offset, show);
2113
+ goto out;
10662114 }
10672115
10682116 switch (nr_bits) {
2117
+ case 128:
2118
+ btf_int128_print(show, safe_data);
2119
+ break;
10692120 case 64:
10702121 if (sign)
1071
- seq_printf(m, "%lld", *(s64 *)data);
2122
+ btf_show_type_value(show, "%lld", *(s64 *)safe_data);
10722123 else
1073
- seq_printf(m, "%llu", *(u64 *)data);
2124
+ btf_show_type_value(show, "%llu", *(u64 *)safe_data);
10742125 break;
10752126 case 32:
10762127 if (sign)
1077
- seq_printf(m, "%d", *(s32 *)data);
2128
+ btf_show_type_value(show, "%d", *(s32 *)safe_data);
10782129 else
1079
- seq_printf(m, "%u", *(u32 *)data);
2130
+ btf_show_type_value(show, "%u", *(u32 *)safe_data);
10802131 break;
10812132 case 16:
10822133 if (sign)
1083
- seq_printf(m, "%d", *(s16 *)data);
2134
+ btf_show_type_value(show, "%d", *(s16 *)safe_data);
10842135 else
1085
- seq_printf(m, "%u", *(u16 *)data);
2136
+ btf_show_type_value(show, "%u", *(u16 *)safe_data);
10862137 break;
10872138 case 8:
2139
+ if (show->state.array_encoding == BTF_INT_CHAR) {
2140
+ /* check for null terminator */
2141
+ if (show->state.array_terminated)
2142
+ break;
2143
+ if (*(char *)data == '\0') {
2144
+ show->state.array_terminated = 1;
2145
+ break;
2146
+ }
2147
+ if (isprint(*(char *)data)) {
2148
+ btf_show_type_value(show, "'%c'",
2149
+ *(char *)safe_data);
2150
+ break;
2151
+ }
2152
+ }
10882153 if (sign)
1089
- seq_printf(m, "%d", *(s8 *)data);
2154
+ btf_show_type_value(show, "%d", *(s8 *)safe_data);
10902155 else
1091
- seq_printf(m, "%u", *(u8 *)data);
2156
+ btf_show_type_value(show, "%u", *(u8 *)safe_data);
10922157 break;
10932158 default:
1094
- btf_int_bits_seq_show(btf, t, data, bits_offset, m);
2159
+ btf_int_bits_show(btf, t, safe_data, bits_offset, show);
2160
+ break;
10952161 }
2162
+out:
2163
+ btf_show_end_type(show);
10962164 }
10972165
10982166 static const struct btf_kind_operations int_ops = {
10992167 .check_meta = btf_int_check_meta,
11002168 .resolve = btf_df_resolve,
11012169 .check_member = btf_int_check_member,
2170
+ .check_kflag_member = btf_int_check_kflag_member,
11022171 .log_details = btf_int_log,
1103
- .seq_show = btf_int_seq_show,
2172
+ .show = btf_int_show,
11042173 };
11052174
11062175 static int btf_modifier_check_member(struct btf_verifier_env *env,
....@@ -1126,6 +2195,31 @@
11262195 return btf_type_ops(resolved_type)->check_member(env, struct_type,
11272196 &resolved_member,
11282197 resolved_type);
2198
+}
2199
+
2200
+static int btf_modifier_check_kflag_member(struct btf_verifier_env *env,
2201
+ const struct btf_type *struct_type,
2202
+ const struct btf_member *member,
2203
+ const struct btf_type *member_type)
2204
+{
2205
+ const struct btf_type *resolved_type;
2206
+ u32 resolved_type_id = member->type;
2207
+ struct btf_member resolved_member;
2208
+ struct btf *btf = env->btf;
2209
+
2210
+ resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL);
2211
+ if (!resolved_type) {
2212
+ btf_verifier_log_member(env, struct_type, member,
2213
+ "Invalid member");
2214
+ return -EINVAL;
2215
+ }
2216
+
2217
+ resolved_member = *member;
2218
+ resolved_member.type = resolved_type_id;
2219
+
2220
+ return btf_type_ops(resolved_type)->check_kflag_member(env, struct_type,
2221
+ &resolved_member,
2222
+ resolved_type);
11292223 }
11302224
11312225 static int btf_ptr_check_member(struct btf_verifier_env *env,
....@@ -1163,6 +2257,11 @@
11632257 return -EINVAL;
11642258 }
11652259
2260
+ if (btf_type_kflag(t)) {
2261
+ btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
2262
+ return -EINVAL;
2263
+ }
2264
+
11662265 if (!BTF_TYPE_ID_VALID(t->type)) {
11672266 btf_verifier_log_type(env, t, "Invalid type_id");
11682267 return -EINVAL;
....@@ -1196,17 +2295,12 @@
11962295 const struct btf_type *next_type;
11972296 u32 next_type_id = t->type;
11982297 struct btf *btf = env->btf;
1199
- u32 next_type_size = 0;
12002298
12012299 next_type = btf_type_by_id(btf, next_type_id);
1202
- if (!next_type) {
2300
+ if (!next_type || btf_type_is_resolve_source_only(next_type)) {
12032301 btf_verifier_log_type(env, v->t, "Invalid type_id");
12042302 return -EINVAL;
12052303 }
1206
-
1207
- /* "typedef void new_void", "const void"...etc */
1208
- if (btf_type_is_void(next_type))
1209
- goto resolved;
12102304
12112305 if (!env_type_is_resolve_sink(env, next_type) &&
12122306 !env_type_is_resolved(env, next_type_id))
....@@ -1218,14 +2312,66 @@
12182312 * save us a few type-following when we use it later (e.g. in
12192313 * pretty print).
12202314 */
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))) {
2315
+ if (!btf_type_id_size(btf, &next_type_id, NULL)) {
2316
+ if (env_type_is_resolved(env, next_type_id))
2317
+ next_type = btf_type_id_resolve(btf, &next_type_id);
2318
+
2319
+ /* "typedef void new_void", "const void"...etc */
2320
+ if (!btf_type_is_void(next_type) &&
2321
+ !btf_type_is_fwd(next_type) &&
2322
+ !btf_type_is_func_proto(next_type)) {
2323
+ btf_verifier_log_type(env, v->t, "Invalid type_id");
2324
+ return -EINVAL;
2325
+ }
2326
+ }
2327
+
2328
+ env_stack_pop_resolved(env, next_type_id, 0);
2329
+
2330
+ return 0;
2331
+}
2332
+
2333
+static int btf_var_resolve(struct btf_verifier_env *env,
2334
+ const struct resolve_vertex *v)
2335
+{
2336
+ const struct btf_type *next_type;
2337
+ const struct btf_type *t = v->t;
2338
+ u32 next_type_id = t->type;
2339
+ struct btf *btf = env->btf;
2340
+
2341
+ next_type = btf_type_by_id(btf, next_type_id);
2342
+ if (!next_type || btf_type_is_resolve_source_only(next_type)) {
12232343 btf_verifier_log_type(env, v->t, "Invalid type_id");
12242344 return -EINVAL;
12252345 }
12262346
1227
-resolved:
1228
- env_stack_pop_resolved(env, next_type_id, next_type_size);
2347
+ if (!env_type_is_resolve_sink(env, next_type) &&
2348
+ !env_type_is_resolved(env, next_type_id))
2349
+ return env_stack_push(env, next_type, next_type_id);
2350
+
2351
+ if (btf_type_is_modifier(next_type)) {
2352
+ const struct btf_type *resolved_type;
2353
+ u32 resolved_type_id;
2354
+
2355
+ resolved_type_id = next_type_id;
2356
+ resolved_type = btf_type_id_resolve(btf, &resolved_type_id);
2357
+
2358
+ if (btf_type_is_ptr(resolved_type) &&
2359
+ !env_type_is_resolve_sink(env, resolved_type) &&
2360
+ !env_type_is_resolved(env, resolved_type_id))
2361
+ return env_stack_push(env, resolved_type,
2362
+ resolved_type_id);
2363
+ }
2364
+
2365
+ /* We must resolve to something concrete at this point, no
2366
+ * forward types or similar that would resolve to size of
2367
+ * zero is allowed.
2368
+ */
2369
+ if (!btf_type_id_size(btf, &next_type_id, NULL)) {
2370
+ btf_verifier_log_type(env, v->t, "Invalid type_id");
2371
+ return -EINVAL;
2372
+ }
2373
+
2374
+ env_stack_pop_resolved(env, next_type_id, 0);
12292375
12302376 return 0;
12312377 }
....@@ -1237,17 +2383,12 @@
12372383 const struct btf_type *t = v->t;
12382384 u32 next_type_id = t->type;
12392385 struct btf *btf = env->btf;
1240
- u32 next_type_size = 0;
12412386
12422387 next_type = btf_type_by_id(btf, next_type_id);
1243
- if (!next_type) {
2388
+ if (!next_type || btf_type_is_resolve_source_only(next_type)) {
12442389 btf_verifier_log_type(env, v->t, "Invalid type_id");
12452390 return -EINVAL;
12462391 }
1247
-
1248
- /* "void *" */
1249
- if (btf_type_is_void(next_type))
1250
- goto resolved;
12512392
12522393 if (!env_type_is_resolve_sink(env, next_type) &&
12532394 !env_type_is_resolved(env, next_type_id))
....@@ -1275,34 +2416,61 @@
12752416 resolved_type_id);
12762417 }
12772418
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;
2419
+ if (!btf_type_id_size(btf, &next_type_id, NULL)) {
2420
+ if (env_type_is_resolved(env, next_type_id))
2421
+ next_type = btf_type_id_resolve(btf, &next_type_id);
2422
+
2423
+ if (!btf_type_is_void(next_type) &&
2424
+ !btf_type_is_fwd(next_type) &&
2425
+ !btf_type_is_func_proto(next_type)) {
2426
+ btf_verifier_log_type(env, v->t, "Invalid type_id");
2427
+ return -EINVAL;
2428
+ }
12822429 }
12832430
1284
-resolved:
12852431 env_stack_pop_resolved(env, next_type_id, 0);
12862432
12872433 return 0;
12882434 }
12892435
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)
2436
+static void btf_modifier_show(const struct btf *btf,
2437
+ const struct btf_type *t,
2438
+ u32 type_id, void *data,
2439
+ u8 bits_offset, struct btf_show *show)
2440
+{
2441
+ if (btf->resolved_ids)
2442
+ t = btf_type_id_resolve(btf, &type_id);
2443
+ else
2444
+ t = btf_type_skip_modifiers(btf, type_id, NULL);
2445
+
2446
+ btf_type_ops(t)->show(btf, t, type_id, data, bits_offset, show);
2447
+}
2448
+
2449
+static void btf_var_show(const struct btf *btf, const struct btf_type *t,
2450
+ u32 type_id, void *data, u8 bits_offset,
2451
+ struct btf_show *show)
12942452 {
12952453 t = btf_type_id_resolve(btf, &type_id);
12962454
1297
- btf_type_ops(t)->seq_show(btf, t, type_id, data, bits_offset, m);
2455
+ btf_type_ops(t)->show(btf, t, type_id, data, bits_offset, show);
12982456 }
12992457
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)
2458
+static void btf_ptr_show(const struct btf *btf, const struct btf_type *t,
2459
+ u32 type_id, void *data, u8 bits_offset,
2460
+ struct btf_show *show)
13032461 {
1304
- /* It is a hashed value */
1305
- seq_printf(m, "%p", *(void **)data);
2462
+ void *safe_data;
2463
+
2464
+ safe_data = btf_show_start_type(show, t, type_id, data);
2465
+ if (!safe_data)
2466
+ return;
2467
+
2468
+ /* It is a hashed value unless BTF_SHOW_PTR_RAW is specified */
2469
+ if (show->flags & BTF_SHOW_PTR_RAW)
2470
+ btf_show_type_value(show, "0x%px", *(void **)safe_data);
2471
+ else
2472
+ btf_show_type_value(show, "0x%p", *(void **)safe_data);
2473
+ btf_show_end_type(show);
13062474 }
13072475
13082476 static void btf_ref_type_log(struct btf_verifier_env *env,
....@@ -1315,16 +2483,18 @@
13152483 .check_meta = btf_ref_type_check_meta,
13162484 .resolve = btf_modifier_resolve,
13172485 .check_member = btf_modifier_check_member,
2486
+ .check_kflag_member = btf_modifier_check_kflag_member,
13182487 .log_details = btf_ref_type_log,
1319
- .seq_show = btf_modifier_seq_show,
2488
+ .show = btf_modifier_show,
13202489 };
13212490
13222491 static struct btf_kind_operations ptr_ops = {
13232492 .check_meta = btf_ref_type_check_meta,
13242493 .resolve = btf_ptr_resolve,
13252494 .check_member = btf_ptr_check_member,
2495
+ .check_kflag_member = btf_generic_check_kflag_member,
13262496 .log_details = btf_ref_type_log,
1327
- .seq_show = btf_ptr_seq_show,
2497
+ .show = btf_ptr_show,
13282498 };
13292499
13302500 static s32 btf_fwd_check_meta(struct btf_verifier_env *env,
....@@ -1353,12 +2523,19 @@
13532523 return 0;
13542524 }
13552525
2526
+static void btf_fwd_type_log(struct btf_verifier_env *env,
2527
+ const struct btf_type *t)
2528
+{
2529
+ btf_verifier_log(env, "%s", btf_type_kflag(t) ? "union" : "struct");
2530
+}
2531
+
13562532 static struct btf_kind_operations fwd_ops = {
13572533 .check_meta = btf_fwd_check_meta,
13582534 .resolve = btf_df_resolve,
13592535 .check_member = btf_df_check_member,
1360
- .log_details = btf_ref_type_log,
1361
- .seq_show = btf_df_seq_show,
2536
+ .check_kflag_member = btf_df_check_kflag_member,
2537
+ .log_details = btf_fwd_type_log,
2538
+ .show = btf_df_show,
13622539 };
13632540
13642541 static int btf_array_check_member(struct btf_verifier_env *env,
....@@ -1415,6 +2592,11 @@
14152592 return -EINVAL;
14162593 }
14172594
2595
+ if (btf_type_kflag(t)) {
2596
+ btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
2597
+ return -EINVAL;
2598
+ }
2599
+
14182600 if (t->size) {
14192601 btf_verifier_log_type(env, t, "size != 0");
14202602 return -EINVAL;
....@@ -1450,7 +2632,8 @@
14502632 /* Check array->index_type */
14512633 index_type_id = array->index_type;
14522634 index_type = btf_type_by_id(btf, index_type_id);
1453
- if (btf_type_is_void_or_null(index_type)) {
2635
+ if (btf_type_nosize_or_null(index_type) ||
2636
+ btf_type_is_resolve_source_only(index_type)) {
14542637 btf_verifier_log_type(env, v->t, "Invalid index");
14552638 return -EINVAL;
14562639 }
....@@ -1469,7 +2652,8 @@
14692652 /* Check array->type */
14702653 elem_type_id = array->type;
14712654 elem_type = btf_type_by_id(btf, elem_type_id);
1472
- if (btf_type_is_void_or_null(elem_type)) {
2655
+ if (btf_type_nosize_or_null(elem_type) ||
2656
+ btf_type_is_resolve_source_only(elem_type)) {
14732657 btf_verifier_log_type(env, v->t,
14742658 "Invalid elem");
14752659 return -EINVAL;
....@@ -1510,36 +2694,99 @@
15102694 array->type, array->index_type, array->nelems);
15112695 }
15122696
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)
2697
+static void __btf_array_show(const struct btf *btf, const struct btf_type *t,
2698
+ u32 type_id, void *data, u8 bits_offset,
2699
+ struct btf_show *show)
15162700 {
15172701 const struct btf_array *array = btf_type_array(t);
15182702 const struct btf_kind_operations *elem_ops;
15192703 const struct btf_type *elem_type;
1520
- u32 i, elem_size, elem_type_id;
2704
+ u32 i, elem_size = 0, elem_type_id;
2705
+ u16 encoding = 0;
15212706
15222707 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, ",");
2708
+ elem_type = btf_type_skip_modifiers(btf, elem_type_id, NULL);
2709
+ if (elem_type && btf_type_has_size(elem_type))
2710
+ elem_size = elem_type->size;
15292711
1530
- elem_ops->seq_show(btf, elem_type, elem_type_id, data,
1531
- bits_offset, m);
1532
- data += elem_size;
2712
+ if (elem_type && btf_type_is_int(elem_type)) {
2713
+ u32 int_type = btf_type_int(elem_type);
2714
+
2715
+ encoding = BTF_INT_ENCODING(int_type);
2716
+
2717
+ /*
2718
+ * BTF_INT_CHAR encoding never seems to be set for
2719
+ * char arrays, so if size is 1 and element is
2720
+ * printable as a char, we'll do that.
2721
+ */
2722
+ if (elem_size == 1)
2723
+ encoding = BTF_INT_CHAR;
15332724 }
1534
- seq_puts(m, "]");
2725
+
2726
+ if (!btf_show_start_array_type(show, t, type_id, encoding, data))
2727
+ return;
2728
+
2729
+ if (!elem_type)
2730
+ goto out;
2731
+ elem_ops = btf_type_ops(elem_type);
2732
+
2733
+ for (i = 0; i < array->nelems; i++) {
2734
+
2735
+ btf_show_start_array_member(show);
2736
+
2737
+ elem_ops->show(btf, elem_type, elem_type_id, data,
2738
+ bits_offset, show);
2739
+ data += elem_size;
2740
+
2741
+ btf_show_end_array_member(show);
2742
+
2743
+ if (show->state.array_terminated)
2744
+ break;
2745
+ }
2746
+out:
2747
+ btf_show_end_array_type(show);
2748
+}
2749
+
2750
+static void btf_array_show(const struct btf *btf, const struct btf_type *t,
2751
+ u32 type_id, void *data, u8 bits_offset,
2752
+ struct btf_show *show)
2753
+{
2754
+ const struct btf_member *m = show->state.member;
2755
+
2756
+ /*
2757
+ * First check if any members would be shown (are non-zero).
2758
+ * See comments above "struct btf_show" definition for more
2759
+ * details on how this works at a high-level.
2760
+ */
2761
+ if (show->state.depth > 0 && !(show->flags & BTF_SHOW_ZERO)) {
2762
+ if (!show->state.depth_check) {
2763
+ show->state.depth_check = show->state.depth + 1;
2764
+ show->state.depth_to_show = 0;
2765
+ }
2766
+ __btf_array_show(btf, t, type_id, data, bits_offset, show);
2767
+ show->state.member = m;
2768
+
2769
+ if (show->state.depth_check != show->state.depth + 1)
2770
+ return;
2771
+ show->state.depth_check = 0;
2772
+
2773
+ if (show->state.depth_to_show <= show->state.depth)
2774
+ return;
2775
+ /*
2776
+ * Reaching here indicates we have recursed and found
2777
+ * non-zero array member(s).
2778
+ */
2779
+ }
2780
+ __btf_array_show(btf, t, type_id, data, bits_offset, show);
15352781 }
15362782
15372783 static struct btf_kind_operations array_ops = {
15382784 .check_meta = btf_array_check_meta,
15392785 .resolve = btf_array_resolve,
15402786 .check_member = btf_array_check_member,
2787
+ .check_kflag_member = btf_generic_check_kflag_member,
15412788 .log_details = btf_array_log,
1542
- .seq_show = btf_array_seq_show,
2789
+ .show = btf_array_show,
15432790 };
15442791
15452792 static int btf_struct_check_member(struct btf_verifier_env *env,
....@@ -1576,6 +2823,7 @@
15762823 u32 meta_needed, last_offset;
15772824 struct btf *btf = env->btf;
15782825 u32 struct_size = t->size;
2826
+ u32 offset;
15792827 u16 i;
15802828
15812829 meta_needed = btf_type_vlen(t) * sizeof(*member);
....@@ -1617,7 +2865,8 @@
16172865 return -EINVAL;
16182866 }
16192867
1620
- if (is_union && member->offset) {
2868
+ offset = btf_member_bit_offset(t, member);
2869
+ if (is_union && offset) {
16212870 btf_verifier_log_member(env, t, member,
16222871 "Invalid member bits_offset");
16232872 return -EINVAL;
....@@ -1627,20 +2876,20 @@
16272876 * ">" instead of ">=" because the last member could be
16282877 * "char a[0];"
16292878 */
1630
- if (last_offset > member->offset) {
2879
+ if (last_offset > offset) {
16312880 btf_verifier_log_member(env, t, member,
16322881 "Invalid member bits_offset");
16332882 return -EINVAL;
16342883 }
16352884
1636
- if (BITS_ROUNDUP_BYTES(member->offset) > struct_size) {
2885
+ if (BITS_ROUNDUP_BYTES(offset) > struct_size) {
16372886 btf_verifier_log_member(env, t, member,
1638
- "Memmber bits_offset exceeds its struct size");
2887
+ "Member bits_offset exceeds its struct size");
16392888 return -EINVAL;
16402889 }
16412890
16422891 btf_verifier_log_member(env, t, member, NULL);
1643
- last_offset = member->offset;
2892
+ last_offset = offset;
16442893 }
16452894
16462895 return meta_needed;
....@@ -1660,7 +2909,7 @@
16602909 if (v->next_member) {
16612910 const struct btf_type *last_member_type;
16622911 const struct btf_member *last_member;
1663
- u16 last_member_type_id;
2912
+ u32 last_member_type_id;
16642913
16652914 last_member = btf_type_member(v->t) + v->next_member - 1;
16662915 last_member_type_id = last_member->type;
....@@ -1670,9 +2919,14 @@
16702919
16712920 last_member_type = btf_type_by_id(env->btf,
16722921 last_member_type_id);
1673
- err = btf_type_ops(last_member_type)->check_member(env, v->t,
1674
- last_member,
1675
- last_member_type);
2922
+ if (btf_type_kflag(v->t))
2923
+ err = btf_type_ops(last_member_type)->check_kflag_member(env, v->t,
2924
+ last_member,
2925
+ last_member_type);
2926
+ else
2927
+ err = btf_type_ops(last_member_type)->check_member(env, v->t,
2928
+ last_member,
2929
+ last_member_type);
16762930 if (err)
16772931 return err;
16782932 }
....@@ -1682,7 +2936,8 @@
16822936 const struct btf_type *member_type = btf_type_by_id(env->btf,
16832937 member_type_id);
16842938
1685
- if (btf_type_is_void_or_null(member_type)) {
2939
+ if (btf_type_nosize_or_null(member_type) ||
2940
+ btf_type_is_resolve_source_only(member_type)) {
16862941 btf_verifier_log_member(env, v->t, member,
16872942 "Invalid member");
16882943 return -EINVAL;
....@@ -1694,9 +2949,14 @@
16942949 return env_stack_push(env, member_type, member_type_id);
16952950 }
16962951
1697
- err = btf_type_ops(member_type)->check_member(env, v->t,
1698
- member,
1699
- member_type);
2952
+ if (btf_type_kflag(v->t))
2953
+ err = btf_type_ops(member_type)->check_kflag_member(env, v->t,
2954
+ member,
2955
+ member_type);
2956
+ else
2957
+ err = btf_type_ops(member_type)->check_member(env, v->t,
2958
+ member,
2959
+ member_type);
17002960 if (err)
17012961 return err;
17022962 }
....@@ -1712,39 +2972,131 @@
17122972 btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t));
17132973 }
17142974
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)
2975
+/* find 'struct bpf_spin_lock' in map value.
2976
+ * return >= 0 offset if found
2977
+ * and < 0 in case of error
2978
+ */
2979
+int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t)
17182980 {
1719
- const char *seq = BTF_INFO_KIND(t->info) == BTF_KIND_UNION ? "|" : ",";
17202981 const struct btf_member *member;
2982
+ u32 i, off = -ENOENT;
2983
+
2984
+ if (!__btf_type_is_struct(t))
2985
+ return -EINVAL;
2986
+
2987
+ for_each_member(i, t, member) {
2988
+ const struct btf_type *member_type = btf_type_by_id(btf,
2989
+ member->type);
2990
+ if (!__btf_type_is_struct(member_type))
2991
+ continue;
2992
+ if (member_type->size != sizeof(struct bpf_spin_lock))
2993
+ continue;
2994
+ if (strcmp(__btf_name_by_offset(btf, member_type->name_off),
2995
+ "bpf_spin_lock"))
2996
+ continue;
2997
+ if (off != -ENOENT)
2998
+ /* only one 'struct bpf_spin_lock' is allowed */
2999
+ return -E2BIG;
3000
+ off = btf_member_bit_offset(t, member);
3001
+ if (off % 8)
3002
+ /* valid C code cannot generate such BTF */
3003
+ return -EINVAL;
3004
+ off /= 8;
3005
+ if (off % __alignof__(struct bpf_spin_lock))
3006
+ /* valid struct bpf_spin_lock will be 4 byte aligned */
3007
+ return -EINVAL;
3008
+ }
3009
+ return off;
3010
+}
3011
+
3012
+static void __btf_struct_show(const struct btf *btf, const struct btf_type *t,
3013
+ u32 type_id, void *data, u8 bits_offset,
3014
+ struct btf_show *show)
3015
+{
3016
+ const struct btf_member *member;
3017
+ void *safe_data;
17213018 u32 i;
17223019
1723
- seq_puts(m, "{");
3020
+ safe_data = btf_show_start_struct_type(show, t, type_id, data);
3021
+ if (!safe_data)
3022
+ return;
3023
+
17243024 for_each_member(i, t, member) {
17253025 const struct btf_type *member_type = btf_type_by_id(btf,
17263026 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);
17303027 const struct btf_kind_operations *ops;
3028
+ u32 member_offset, bitfield_size;
3029
+ u32 bytes_offset;
3030
+ u8 bits8_offset;
17313031
1732
- if (i)
1733
- seq_puts(m, seq);
3032
+ btf_show_start_member(show, member);
17343033
1735
- ops = btf_type_ops(member_type);
1736
- ops->seq_show(btf, member_type, member->type,
1737
- data + bytes_offset, bits8_offset, m);
3034
+ member_offset = btf_member_bit_offset(t, member);
3035
+ bitfield_size = btf_member_bitfield_size(t, member);
3036
+ bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset);
3037
+ bits8_offset = BITS_PER_BYTE_MASKED(member_offset);
3038
+ if (bitfield_size) {
3039
+ safe_data = btf_show_start_type(show, member_type,
3040
+ member->type,
3041
+ data + bytes_offset);
3042
+ if (safe_data)
3043
+ btf_bitfield_show(safe_data,
3044
+ bits8_offset,
3045
+ bitfield_size, show);
3046
+ btf_show_end_type(show);
3047
+ } else {
3048
+ ops = btf_type_ops(member_type);
3049
+ ops->show(btf, member_type, member->type,
3050
+ data + bytes_offset, bits8_offset, show);
3051
+ }
3052
+
3053
+ btf_show_end_member(show);
17383054 }
1739
- seq_puts(m, "}");
3055
+
3056
+ btf_show_end_struct_type(show);
3057
+}
3058
+
3059
+static void btf_struct_show(const struct btf *btf, const struct btf_type *t,
3060
+ u32 type_id, void *data, u8 bits_offset,
3061
+ struct btf_show *show)
3062
+{
3063
+ const struct btf_member *m = show->state.member;
3064
+
3065
+ /*
3066
+ * First check if any members would be shown (are non-zero).
3067
+ * See comments above "struct btf_show" definition for more
3068
+ * details on how this works at a high-level.
3069
+ */
3070
+ if (show->state.depth > 0 && !(show->flags & BTF_SHOW_ZERO)) {
3071
+ if (!show->state.depth_check) {
3072
+ show->state.depth_check = show->state.depth + 1;
3073
+ show->state.depth_to_show = 0;
3074
+ }
3075
+ __btf_struct_show(btf, t, type_id, data, bits_offset, show);
3076
+ /* Restore saved member data here */
3077
+ show->state.member = m;
3078
+ if (show->state.depth_check != show->state.depth + 1)
3079
+ return;
3080
+ show->state.depth_check = 0;
3081
+
3082
+ if (show->state.depth_to_show <= show->state.depth)
3083
+ return;
3084
+ /*
3085
+ * Reaching here indicates we have recursed and found
3086
+ * non-zero child values.
3087
+ */
3088
+ }
3089
+
3090
+ __btf_struct_show(btf, t, type_id, data, bits_offset, show);
17403091 }
17413092
17423093 static struct btf_kind_operations struct_ops = {
17433094 .check_meta = btf_struct_check_meta,
17443095 .resolve = btf_struct_resolve,
17453096 .check_member = btf_struct_check_member,
3097
+ .check_kflag_member = btf_generic_check_kflag_member,
17463098 .log_details = btf_struct_log,
1747
- .seq_show = btf_struct_seq_show,
3099
+ .show = btf_struct_show,
17483100 };
17493101
17503102 static int btf_enum_check_member(struct btf_verifier_env *env,
....@@ -1772,6 +3124,41 @@
17723124 return 0;
17733125 }
17743126
3127
+static int btf_enum_check_kflag_member(struct btf_verifier_env *env,
3128
+ const struct btf_type *struct_type,
3129
+ const struct btf_member *member,
3130
+ const struct btf_type *member_type)
3131
+{
3132
+ u32 struct_bits_off, nr_bits, bytes_end, struct_size;
3133
+ u32 int_bitsize = sizeof(int) * BITS_PER_BYTE;
3134
+
3135
+ struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset);
3136
+ nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset);
3137
+ if (!nr_bits) {
3138
+ if (BITS_PER_BYTE_MASKED(struct_bits_off)) {
3139
+ btf_verifier_log_member(env, struct_type, member,
3140
+ "Member is not byte aligned");
3141
+ return -EINVAL;
3142
+ }
3143
+
3144
+ nr_bits = int_bitsize;
3145
+ } else if (nr_bits > int_bitsize) {
3146
+ btf_verifier_log_member(env, struct_type, member,
3147
+ "Invalid member bitfield_size");
3148
+ return -EINVAL;
3149
+ }
3150
+
3151
+ struct_size = struct_type->size;
3152
+ bytes_end = BITS_ROUNDUP_BYTES(struct_bits_off + nr_bits);
3153
+ if (struct_size < bytes_end) {
3154
+ btf_verifier_log_member(env, struct_type, member,
3155
+ "Member exceeds struct_size");
3156
+ return -EINVAL;
3157
+ }
3158
+
3159
+ return 0;
3160
+}
3161
+
17753162 static s32 btf_enum_check_meta(struct btf_verifier_env *env,
17763163 const struct btf_type *t,
17773164 u32 meta_left)
....@@ -1791,9 +3178,13 @@
17913178 return -EINVAL;
17923179 }
17933180
1794
- if (t->size != sizeof(int)) {
1795
- btf_verifier_log_type(env, t, "Expected size:%zu",
1796
- sizeof(int));
3181
+ if (btf_type_kflag(t)) {
3182
+ btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
3183
+ return -EINVAL;
3184
+ }
3185
+
3186
+ if (t->size > 8 || !is_power_of_2(t->size)) {
3187
+ btf_verifier_log_type(env, t, "Unexpected size");
17973188 return -EINVAL;
17983189 }
17993190
....@@ -1820,9 +3211,10 @@
18203211 return -EINVAL;
18213212 }
18223213
1823
-
3214
+ if (env->log.level == BPF_LOG_KERNEL)
3215
+ continue;
18243216 btf_verifier_log(env, "\t%s val=%d\n",
1825
- btf_name_by_offset(btf, enums[i].name_off),
3217
+ __btf_name_by_offset(btf, enums[i].name_off),
18263218 enums[i].val);
18273219 }
18283220
....@@ -1835,32 +3227,509 @@
18353227 btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t));
18363228 }
18373229
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)
3230
+static void btf_enum_show(const struct btf *btf, const struct btf_type *t,
3231
+ u32 type_id, void *data, u8 bits_offset,
3232
+ struct btf_show *show)
18413233 {
18423234 const struct btf_enum *enums = btf_type_enum(t);
18433235 u32 i, nr_enums = btf_type_vlen(t);
1844
- int v = *(int *)data;
3236
+ void *safe_data;
3237
+ int v;
3238
+
3239
+ safe_data = btf_show_start_type(show, t, type_id, data);
3240
+ if (!safe_data)
3241
+ return;
3242
+
3243
+ v = *(int *)safe_data;
18453244
18463245 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
- }
3246
+ if (v != enums[i].val)
3247
+ continue;
3248
+
3249
+ btf_show_type_value(show, "%s",
3250
+ __btf_name_by_offset(btf,
3251
+ enums[i].name_off));
3252
+
3253
+ btf_show_end_type(show);
3254
+ return;
18523255 }
18533256
1854
- seq_printf(m, "%d", v);
3257
+ btf_show_type_value(show, "%d", v);
3258
+ btf_show_end_type(show);
18553259 }
18563260
18573261 static struct btf_kind_operations enum_ops = {
18583262 .check_meta = btf_enum_check_meta,
18593263 .resolve = btf_df_resolve,
18603264 .check_member = btf_enum_check_member,
3265
+ .check_kflag_member = btf_enum_check_kflag_member,
18613266 .log_details = btf_enum_log,
1862
- .seq_show = btf_enum_seq_show,
3267
+ .show = btf_enum_show,
18633268 };
3269
+
3270
+static s32 btf_func_proto_check_meta(struct btf_verifier_env *env,
3271
+ const struct btf_type *t,
3272
+ u32 meta_left)
3273
+{
3274
+ u32 meta_needed = btf_type_vlen(t) * sizeof(struct btf_param);
3275
+
3276
+ if (meta_left < meta_needed) {
3277
+ btf_verifier_log_basic(env, t,
3278
+ "meta_left:%u meta_needed:%u",
3279
+ meta_left, meta_needed);
3280
+ return -EINVAL;
3281
+ }
3282
+
3283
+ if (t->name_off) {
3284
+ btf_verifier_log_type(env, t, "Invalid name");
3285
+ return -EINVAL;
3286
+ }
3287
+
3288
+ if (btf_type_kflag(t)) {
3289
+ btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
3290
+ return -EINVAL;
3291
+ }
3292
+
3293
+ btf_verifier_log_type(env, t, NULL);
3294
+
3295
+ return meta_needed;
3296
+}
3297
+
3298
+static void btf_func_proto_log(struct btf_verifier_env *env,
3299
+ const struct btf_type *t)
3300
+{
3301
+ const struct btf_param *args = (const struct btf_param *)(t + 1);
3302
+ u16 nr_args = btf_type_vlen(t), i;
3303
+
3304
+ btf_verifier_log(env, "return=%u args=(", t->type);
3305
+ if (!nr_args) {
3306
+ btf_verifier_log(env, "void");
3307
+ goto done;
3308
+ }
3309
+
3310
+ if (nr_args == 1 && !args[0].type) {
3311
+ /* Only one vararg */
3312
+ btf_verifier_log(env, "vararg");
3313
+ goto done;
3314
+ }
3315
+
3316
+ btf_verifier_log(env, "%u %s", args[0].type,
3317
+ __btf_name_by_offset(env->btf,
3318
+ args[0].name_off));
3319
+ for (i = 1; i < nr_args - 1; i++)
3320
+ btf_verifier_log(env, ", %u %s", args[i].type,
3321
+ __btf_name_by_offset(env->btf,
3322
+ args[i].name_off));
3323
+
3324
+ if (nr_args > 1) {
3325
+ const struct btf_param *last_arg = &args[nr_args - 1];
3326
+
3327
+ if (last_arg->type)
3328
+ btf_verifier_log(env, ", %u %s", last_arg->type,
3329
+ __btf_name_by_offset(env->btf,
3330
+ last_arg->name_off));
3331
+ else
3332
+ btf_verifier_log(env, ", vararg");
3333
+ }
3334
+
3335
+done:
3336
+ btf_verifier_log(env, ")");
3337
+}
3338
+
3339
+static struct btf_kind_operations func_proto_ops = {
3340
+ .check_meta = btf_func_proto_check_meta,
3341
+ .resolve = btf_df_resolve,
3342
+ /*
3343
+ * BTF_KIND_FUNC_PROTO cannot be directly referred by
3344
+ * a struct's member.
3345
+ *
3346
+ * It should be a funciton pointer instead.
3347
+ * (i.e. struct's member -> BTF_KIND_PTR -> BTF_KIND_FUNC_PROTO)
3348
+ *
3349
+ * Hence, there is no btf_func_check_member().
3350
+ */
3351
+ .check_member = btf_df_check_member,
3352
+ .check_kflag_member = btf_df_check_kflag_member,
3353
+ .log_details = btf_func_proto_log,
3354
+ .show = btf_df_show,
3355
+};
3356
+
3357
+static s32 btf_func_check_meta(struct btf_verifier_env *env,
3358
+ const struct btf_type *t,
3359
+ u32 meta_left)
3360
+{
3361
+ if (!t->name_off ||
3362
+ !btf_name_valid_identifier(env->btf, t->name_off)) {
3363
+ btf_verifier_log_type(env, t, "Invalid name");
3364
+ return -EINVAL;
3365
+ }
3366
+
3367
+ if (btf_type_vlen(t) > BTF_FUNC_GLOBAL) {
3368
+ btf_verifier_log_type(env, t, "Invalid func linkage");
3369
+ return -EINVAL;
3370
+ }
3371
+
3372
+ if (btf_type_kflag(t)) {
3373
+ btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
3374
+ return -EINVAL;
3375
+ }
3376
+
3377
+ btf_verifier_log_type(env, t, NULL);
3378
+
3379
+ return 0;
3380
+}
3381
+
3382
+static struct btf_kind_operations func_ops = {
3383
+ .check_meta = btf_func_check_meta,
3384
+ .resolve = btf_df_resolve,
3385
+ .check_member = btf_df_check_member,
3386
+ .check_kflag_member = btf_df_check_kflag_member,
3387
+ .log_details = btf_ref_type_log,
3388
+ .show = btf_df_show,
3389
+};
3390
+
3391
+static s32 btf_var_check_meta(struct btf_verifier_env *env,
3392
+ const struct btf_type *t,
3393
+ u32 meta_left)
3394
+{
3395
+ const struct btf_var *var;
3396
+ u32 meta_needed = sizeof(*var);
3397
+
3398
+ if (meta_left < meta_needed) {
3399
+ btf_verifier_log_basic(env, t,
3400
+ "meta_left:%u meta_needed:%u",
3401
+ meta_left, meta_needed);
3402
+ return -EINVAL;
3403
+ }
3404
+
3405
+ if (btf_type_vlen(t)) {
3406
+ btf_verifier_log_type(env, t, "vlen != 0");
3407
+ return -EINVAL;
3408
+ }
3409
+
3410
+ if (btf_type_kflag(t)) {
3411
+ btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
3412
+ return -EINVAL;
3413
+ }
3414
+
3415
+ if (!t->name_off ||
3416
+ !__btf_name_valid(env->btf, t->name_off)) {
3417
+ btf_verifier_log_type(env, t, "Invalid name");
3418
+ return -EINVAL;
3419
+ }
3420
+
3421
+ /* A var cannot be in type void */
3422
+ if (!t->type || !BTF_TYPE_ID_VALID(t->type)) {
3423
+ btf_verifier_log_type(env, t, "Invalid type_id");
3424
+ return -EINVAL;
3425
+ }
3426
+
3427
+ var = btf_type_var(t);
3428
+ if (var->linkage != BTF_VAR_STATIC &&
3429
+ var->linkage != BTF_VAR_GLOBAL_ALLOCATED) {
3430
+ btf_verifier_log_type(env, t, "Linkage not supported");
3431
+ return -EINVAL;
3432
+ }
3433
+
3434
+ btf_verifier_log_type(env, t, NULL);
3435
+
3436
+ return meta_needed;
3437
+}
3438
+
3439
+static void btf_var_log(struct btf_verifier_env *env, const struct btf_type *t)
3440
+{
3441
+ const struct btf_var *var = btf_type_var(t);
3442
+
3443
+ btf_verifier_log(env, "type_id=%u linkage=%u", t->type, var->linkage);
3444
+}
3445
+
3446
+static const struct btf_kind_operations var_ops = {
3447
+ .check_meta = btf_var_check_meta,
3448
+ .resolve = btf_var_resolve,
3449
+ .check_member = btf_df_check_member,
3450
+ .check_kflag_member = btf_df_check_kflag_member,
3451
+ .log_details = btf_var_log,
3452
+ .show = btf_var_show,
3453
+};
3454
+
3455
+static s32 btf_datasec_check_meta(struct btf_verifier_env *env,
3456
+ const struct btf_type *t,
3457
+ u32 meta_left)
3458
+{
3459
+ const struct btf_var_secinfo *vsi;
3460
+ u64 last_vsi_end_off = 0, sum = 0;
3461
+ u32 i, meta_needed;
3462
+
3463
+ meta_needed = btf_type_vlen(t) * sizeof(*vsi);
3464
+ if (meta_left < meta_needed) {
3465
+ btf_verifier_log_basic(env, t,
3466
+ "meta_left:%u meta_needed:%u",
3467
+ meta_left, meta_needed);
3468
+ return -EINVAL;
3469
+ }
3470
+
3471
+ if (!btf_type_vlen(t)) {
3472
+ btf_verifier_log_type(env, t, "vlen == 0");
3473
+ return -EINVAL;
3474
+ }
3475
+
3476
+ if (!t->size) {
3477
+ btf_verifier_log_type(env, t, "size == 0");
3478
+ return -EINVAL;
3479
+ }
3480
+
3481
+ if (btf_type_kflag(t)) {
3482
+ btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
3483
+ return -EINVAL;
3484
+ }
3485
+
3486
+ if (!t->name_off ||
3487
+ !btf_name_valid_section(env->btf, t->name_off)) {
3488
+ btf_verifier_log_type(env, t, "Invalid name");
3489
+ return -EINVAL;
3490
+ }
3491
+
3492
+ btf_verifier_log_type(env, t, NULL);
3493
+
3494
+ for_each_vsi(i, t, vsi) {
3495
+ /* A var cannot be in type void */
3496
+ if (!vsi->type || !BTF_TYPE_ID_VALID(vsi->type)) {
3497
+ btf_verifier_log_vsi(env, t, vsi,
3498
+ "Invalid type_id");
3499
+ return -EINVAL;
3500
+ }
3501
+
3502
+ if (vsi->offset < last_vsi_end_off || vsi->offset >= t->size) {
3503
+ btf_verifier_log_vsi(env, t, vsi,
3504
+ "Invalid offset");
3505
+ return -EINVAL;
3506
+ }
3507
+
3508
+ if (!vsi->size || vsi->size > t->size) {
3509
+ btf_verifier_log_vsi(env, t, vsi,
3510
+ "Invalid size");
3511
+ return -EINVAL;
3512
+ }
3513
+
3514
+ last_vsi_end_off = vsi->offset + vsi->size;
3515
+ if (last_vsi_end_off > t->size) {
3516
+ btf_verifier_log_vsi(env, t, vsi,
3517
+ "Invalid offset+size");
3518
+ return -EINVAL;
3519
+ }
3520
+
3521
+ btf_verifier_log_vsi(env, t, vsi, NULL);
3522
+ sum += vsi->size;
3523
+ }
3524
+
3525
+ if (t->size < sum) {
3526
+ btf_verifier_log_type(env, t, "Invalid btf_info size");
3527
+ return -EINVAL;
3528
+ }
3529
+
3530
+ return meta_needed;
3531
+}
3532
+
3533
+static int btf_datasec_resolve(struct btf_verifier_env *env,
3534
+ const struct resolve_vertex *v)
3535
+{
3536
+ const struct btf_var_secinfo *vsi;
3537
+ struct btf *btf = env->btf;
3538
+ u16 i;
3539
+
3540
+ env->resolve_mode = RESOLVE_TBD;
3541
+ for_each_vsi_from(i, v->next_member, v->t, vsi) {
3542
+ u32 var_type_id = vsi->type, type_id, type_size = 0;
3543
+ const struct btf_type *var_type = btf_type_by_id(env->btf,
3544
+ var_type_id);
3545
+ if (!var_type || !btf_type_is_var(var_type)) {
3546
+ btf_verifier_log_vsi(env, v->t, vsi,
3547
+ "Not a VAR kind member");
3548
+ return -EINVAL;
3549
+ }
3550
+
3551
+ if (!env_type_is_resolve_sink(env, var_type) &&
3552
+ !env_type_is_resolved(env, var_type_id)) {
3553
+ env_stack_set_next_member(env, i + 1);
3554
+ return env_stack_push(env, var_type, var_type_id);
3555
+ }
3556
+
3557
+ type_id = var_type->type;
3558
+ if (!btf_type_id_size(btf, &type_id, &type_size)) {
3559
+ btf_verifier_log_vsi(env, v->t, vsi, "Invalid type");
3560
+ return -EINVAL;
3561
+ }
3562
+
3563
+ if (vsi->size < type_size) {
3564
+ btf_verifier_log_vsi(env, v->t, vsi, "Invalid size");
3565
+ return -EINVAL;
3566
+ }
3567
+ }
3568
+
3569
+ env_stack_pop_resolved(env, 0, 0);
3570
+ return 0;
3571
+}
3572
+
3573
+static void btf_datasec_log(struct btf_verifier_env *env,
3574
+ const struct btf_type *t)
3575
+{
3576
+ btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t));
3577
+}
3578
+
3579
+static void btf_datasec_show(const struct btf *btf,
3580
+ const struct btf_type *t, u32 type_id,
3581
+ void *data, u8 bits_offset,
3582
+ struct btf_show *show)
3583
+{
3584
+ const struct btf_var_secinfo *vsi;
3585
+ const struct btf_type *var;
3586
+ u32 i;
3587
+
3588
+ if (!btf_show_start_type(show, t, type_id, data))
3589
+ return;
3590
+
3591
+ btf_show_type_value(show, "section (\"%s\") = {",
3592
+ __btf_name_by_offset(btf, t->name_off));
3593
+ for_each_vsi(i, t, vsi) {
3594
+ var = btf_type_by_id(btf, vsi->type);
3595
+ if (i)
3596
+ btf_show(show, ",");
3597
+ btf_type_ops(var)->show(btf, var, vsi->type,
3598
+ data + vsi->offset, bits_offset, show);
3599
+ }
3600
+ btf_show_end_type(show);
3601
+}
3602
+
3603
+static const struct btf_kind_operations datasec_ops = {
3604
+ .check_meta = btf_datasec_check_meta,
3605
+ .resolve = btf_datasec_resolve,
3606
+ .check_member = btf_df_check_member,
3607
+ .check_kflag_member = btf_df_check_kflag_member,
3608
+ .log_details = btf_datasec_log,
3609
+ .show = btf_datasec_show,
3610
+};
3611
+
3612
+static int btf_func_proto_check(struct btf_verifier_env *env,
3613
+ const struct btf_type *t)
3614
+{
3615
+ const struct btf_type *ret_type;
3616
+ const struct btf_param *args;
3617
+ const struct btf *btf;
3618
+ u16 nr_args, i;
3619
+ int err;
3620
+
3621
+ btf = env->btf;
3622
+ args = (const struct btf_param *)(t + 1);
3623
+ nr_args = btf_type_vlen(t);
3624
+
3625
+ /* Check func return type which could be "void" (t->type == 0) */
3626
+ if (t->type) {
3627
+ u32 ret_type_id = t->type;
3628
+
3629
+ ret_type = btf_type_by_id(btf, ret_type_id);
3630
+ if (!ret_type) {
3631
+ btf_verifier_log_type(env, t, "Invalid return type");
3632
+ return -EINVAL;
3633
+ }
3634
+
3635
+ if (btf_type_needs_resolve(ret_type) &&
3636
+ !env_type_is_resolved(env, ret_type_id)) {
3637
+ err = btf_resolve(env, ret_type, ret_type_id);
3638
+ if (err)
3639
+ return err;
3640
+ }
3641
+
3642
+ /* Ensure the return type is a type that has a size */
3643
+ if (!btf_type_id_size(btf, &ret_type_id, NULL)) {
3644
+ btf_verifier_log_type(env, t, "Invalid return type");
3645
+ return -EINVAL;
3646
+ }
3647
+ }
3648
+
3649
+ if (!nr_args)
3650
+ return 0;
3651
+
3652
+ /* Last func arg type_id could be 0 if it is a vararg */
3653
+ if (!args[nr_args - 1].type) {
3654
+ if (args[nr_args - 1].name_off) {
3655
+ btf_verifier_log_type(env, t, "Invalid arg#%u",
3656
+ nr_args);
3657
+ return -EINVAL;
3658
+ }
3659
+ nr_args--;
3660
+ }
3661
+
3662
+ err = 0;
3663
+ for (i = 0; i < nr_args; i++) {
3664
+ const struct btf_type *arg_type;
3665
+ u32 arg_type_id;
3666
+
3667
+ arg_type_id = args[i].type;
3668
+ arg_type = btf_type_by_id(btf, arg_type_id);
3669
+ if (!arg_type) {
3670
+ btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1);
3671
+ err = -EINVAL;
3672
+ break;
3673
+ }
3674
+
3675
+ if (btf_type_is_resolve_source_only(arg_type)) {
3676
+ btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1);
3677
+ return -EINVAL;
3678
+ }
3679
+
3680
+ if (args[i].name_off &&
3681
+ (!btf_name_offset_valid(btf, args[i].name_off) ||
3682
+ !btf_name_valid_identifier(btf, args[i].name_off))) {
3683
+ btf_verifier_log_type(env, t,
3684
+ "Invalid arg#%u", i + 1);
3685
+ err = -EINVAL;
3686
+ break;
3687
+ }
3688
+
3689
+ if (btf_type_needs_resolve(arg_type) &&
3690
+ !env_type_is_resolved(env, arg_type_id)) {
3691
+ err = btf_resolve(env, arg_type, arg_type_id);
3692
+ if (err)
3693
+ break;
3694
+ }
3695
+
3696
+ if (!btf_type_id_size(btf, &arg_type_id, NULL)) {
3697
+ btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1);
3698
+ err = -EINVAL;
3699
+ break;
3700
+ }
3701
+ }
3702
+
3703
+ return err;
3704
+}
3705
+
3706
+static int btf_func_check(struct btf_verifier_env *env,
3707
+ const struct btf_type *t)
3708
+{
3709
+ const struct btf_type *proto_type;
3710
+ const struct btf_param *args;
3711
+ const struct btf *btf;
3712
+ u16 nr_args, i;
3713
+
3714
+ btf = env->btf;
3715
+ proto_type = btf_type_by_id(btf, t->type);
3716
+
3717
+ if (!proto_type || !btf_type_is_func_proto(proto_type)) {
3718
+ btf_verifier_log_type(env, t, "Invalid type_id");
3719
+ return -EINVAL;
3720
+ }
3721
+
3722
+ args = (const struct btf_param *)(proto_type + 1);
3723
+ nr_args = btf_type_vlen(proto_type);
3724
+ for (i = 0; i < nr_args; i++) {
3725
+ if (!args[i].name_off && args[i].type) {
3726
+ btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1);
3727
+ return -EINVAL;
3728
+ }
3729
+ }
3730
+
3731
+ return 0;
3732
+}
18643733
18653734 static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = {
18663735 [BTF_KIND_INT] = &int_ops,
....@@ -1874,6 +3743,10 @@
18743743 [BTF_KIND_VOLATILE] = &modifier_ops,
18753744 [BTF_KIND_CONST] = &modifier_ops,
18763745 [BTF_KIND_RESTRICT] = &modifier_ops,
3746
+ [BTF_KIND_FUNC] = &func_ops,
3747
+ [BTF_KIND_FUNC_PROTO] = &func_proto_ops,
3748
+ [BTF_KIND_VAR] = &var_ops,
3749
+ [BTF_KIND_DATASEC] = &datasec_ops,
18773750 };
18783751
18793752 static s32 btf_check_meta(struct btf_verifier_env *env,
....@@ -1945,30 +3818,6 @@
19453818 return 0;
19463819 }
19473820
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
-
19723821 static bool btf_resolve_valid(struct btf_verifier_env *env,
19733822 const struct btf_type *t,
19743823 u32 type_id)
....@@ -1978,13 +3827,17 @@
19783827 if (!env_type_is_resolved(env, type_id))
19793828 return false;
19803829
1981
- if (btf_type_is_struct(t))
3830
+ if (btf_type_is_struct(t) || btf_type_is_datasec(t))
19823831 return !btf->resolved_ids[type_id] &&
1983
- !btf->resolved_sizes[type_id];
3832
+ !btf->resolved_sizes[type_id];
19843833
1985
- if (btf_type_is_modifier(t) || btf_type_is_ptr(t)) {
3834
+ if (btf_type_is_modifier(t) || btf_type_is_ptr(t) ||
3835
+ btf_type_is_var(t)) {
19863836 t = btf_type_id_resolve(btf, &type_id);
1987
- return t && !btf_type_is_modifier(t);
3837
+ return t &&
3838
+ !btf_type_is_modifier(t) &&
3839
+ !btf_type_is_var(t) &&
3840
+ !btf_type_is_datasec(t);
19883841 }
19893842
19903843 if (btf_type_is_array(t)) {
....@@ -2000,6 +3853,39 @@
20003853 }
20013854
20023855 return false;
3856
+}
3857
+
3858
+static int btf_resolve(struct btf_verifier_env *env,
3859
+ const struct btf_type *t, u32 type_id)
3860
+{
3861
+ u32 save_log_type_id = env->log_type_id;
3862
+ const struct resolve_vertex *v;
3863
+ int err = 0;
3864
+
3865
+ env->resolve_mode = RESOLVE_TBD;
3866
+ env_stack_push(env, t, type_id);
3867
+ while (!err && (v = env_stack_peak(env))) {
3868
+ env->log_type_id = v->type_id;
3869
+ err = btf_type_ops(v->t)->resolve(env, v);
3870
+ }
3871
+
3872
+ env->log_type_id = type_id;
3873
+ if (err == -E2BIG) {
3874
+ btf_verifier_log_type(env, t,
3875
+ "Exceeded max resolving depth:%u",
3876
+ MAX_RESOLVE_DEPTH);
3877
+ } else if (err == -EEXIST) {
3878
+ btf_verifier_log_type(env, t, "Loop detected");
3879
+ }
3880
+
3881
+ /* Final sanity check */
3882
+ if (!err && !btf_resolve_valid(env, t, type_id)) {
3883
+ btf_verifier_log_type(env, t, "Invalid resolve state");
3884
+ err = -EINVAL;
3885
+ }
3886
+
3887
+ env->log_type_id = save_log_type_id;
3888
+ return err;
20033889 }
20043890
20053891 static int btf_check_all_types(struct btf_verifier_env *env)
....@@ -2024,10 +3910,16 @@
20243910 return err;
20253911 }
20263912
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;
3913
+ if (btf_type_is_func_proto(t)) {
3914
+ err = btf_func_proto_check(env, t);
3915
+ if (err)
3916
+ return err;
3917
+ }
3918
+
3919
+ if (btf_type_is_func(t)) {
3920
+ err = btf_func_check(env, t);
3921
+ if (err)
3922
+ return err;
20313923 }
20323924 }
20333925
....@@ -2190,9 +4082,6 @@
21904082
21914083 hdr = &btf->hdr;
21924084
2193
- if (hdr->hdr_len != hdr_len)
2194
- return -EINVAL;
2195
-
21964085 btf_verifier_log_hdr(env, btf_data_size);
21974086
21984087 if (hdr->magic != BTF_MAGIC) {
....@@ -2248,8 +4137,7 @@
22484137 log->len_total = log_size;
22494138
22504139 /* log attributes have to be sane */
2251
- if (log->len_total < 128 || log->len_total > UINT_MAX >> 8 ||
2252
- !log->level || !log->ubuf) {
4140
+ if (!bpf_verifier_log_attr_valid(log)) {
22534141 err = -EINVAL;
22544142 goto errout;
22554143 }
....@@ -2306,13 +4194,1241 @@
23064194 return ERR_PTR(err);
23074195 }
23084196
2309
-void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj,
2310
- struct seq_file *m)
4197
+extern char __weak __start_BTF[];
4198
+extern char __weak __stop_BTF[];
4199
+extern struct btf *btf_vmlinux;
4200
+
4201
+#define BPF_MAP_TYPE(_id, _ops)
4202
+#define BPF_LINK_TYPE(_id, _name)
4203
+static union {
4204
+ struct bpf_ctx_convert {
4205
+#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
4206
+ prog_ctx_type _id##_prog; \
4207
+ kern_ctx_type _id##_kern;
4208
+#include <linux/bpf_types.h>
4209
+#undef BPF_PROG_TYPE
4210
+ } *__t;
4211
+ /* 't' is written once under lock. Read many times. */
4212
+ const struct btf_type *t;
4213
+} bpf_ctx_convert;
4214
+enum {
4215
+#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
4216
+ __ctx_convert##_id,
4217
+#include <linux/bpf_types.h>
4218
+#undef BPF_PROG_TYPE
4219
+ __ctx_convert_unused, /* to avoid empty enum in extreme .config */
4220
+};
4221
+static u8 bpf_ctx_convert_map[] = {
4222
+#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
4223
+ [_id] = __ctx_convert##_id,
4224
+#include <linux/bpf_types.h>
4225
+#undef BPF_PROG_TYPE
4226
+ 0, /* avoid empty array */
4227
+};
4228
+#undef BPF_MAP_TYPE
4229
+#undef BPF_LINK_TYPE
4230
+
4231
+static const struct btf_member *
4232
+btf_get_prog_ctx_type(struct bpf_verifier_log *log, struct btf *btf,
4233
+ const struct btf_type *t, enum bpf_prog_type prog_type,
4234
+ int arg)
4235
+{
4236
+ const struct btf_type *conv_struct;
4237
+ const struct btf_type *ctx_struct;
4238
+ const struct btf_member *ctx_type;
4239
+ const char *tname, *ctx_tname;
4240
+
4241
+ conv_struct = bpf_ctx_convert.t;
4242
+ if (!conv_struct) {
4243
+ bpf_log(log, "btf_vmlinux is malformed\n");
4244
+ return NULL;
4245
+ }
4246
+ t = btf_type_by_id(btf, t->type);
4247
+ while (btf_type_is_modifier(t))
4248
+ t = btf_type_by_id(btf, t->type);
4249
+ if (!btf_type_is_struct(t)) {
4250
+ /* Only pointer to struct is supported for now.
4251
+ * That means that BPF_PROG_TYPE_TRACEPOINT with BTF
4252
+ * is not supported yet.
4253
+ * BPF_PROG_TYPE_RAW_TRACEPOINT is fine.
4254
+ */
4255
+ if (log->level & BPF_LOG_LEVEL)
4256
+ bpf_log(log, "arg#%d type is not a struct\n", arg);
4257
+ return NULL;
4258
+ }
4259
+ tname = btf_name_by_offset(btf, t->name_off);
4260
+ if (!tname) {
4261
+ bpf_log(log, "arg#%d struct doesn't have a name\n", arg);
4262
+ return NULL;
4263
+ }
4264
+ /* prog_type is valid bpf program type. No need for bounds check. */
4265
+ ctx_type = btf_type_member(conv_struct) + bpf_ctx_convert_map[prog_type] * 2;
4266
+ /* ctx_struct is a pointer to prog_ctx_type in vmlinux.
4267
+ * Like 'struct __sk_buff'
4268
+ */
4269
+ ctx_struct = btf_type_by_id(btf_vmlinux, ctx_type->type);
4270
+ if (!ctx_struct)
4271
+ /* should not happen */
4272
+ return NULL;
4273
+again:
4274
+ ctx_tname = btf_name_by_offset(btf_vmlinux, ctx_struct->name_off);
4275
+ if (!ctx_tname) {
4276
+ /* should not happen */
4277
+ bpf_log(log, "Please fix kernel include/linux/bpf_types.h\n");
4278
+ return NULL;
4279
+ }
4280
+ /* only compare that prog's ctx type name is the same as
4281
+ * kernel expects. No need to compare field by field.
4282
+ * It's ok for bpf prog to do:
4283
+ * struct __sk_buff {};
4284
+ * int socket_filter_bpf_prog(struct __sk_buff *skb)
4285
+ * { // no fields of skb are ever used }
4286
+ */
4287
+ if (strcmp(ctx_tname, tname)) {
4288
+ /* bpf_user_pt_regs_t is a typedef, so resolve it to
4289
+ * underlying struct and check name again
4290
+ */
4291
+ if (!btf_type_is_modifier(ctx_struct))
4292
+ return NULL;
4293
+ while (btf_type_is_modifier(ctx_struct))
4294
+ ctx_struct = btf_type_by_id(btf_vmlinux, ctx_struct->type);
4295
+ goto again;
4296
+ }
4297
+ return ctx_type;
4298
+}
4299
+
4300
+static const struct bpf_map_ops * const btf_vmlinux_map_ops[] = {
4301
+#define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
4302
+#define BPF_LINK_TYPE(_id, _name)
4303
+#define BPF_MAP_TYPE(_id, _ops) \
4304
+ [_id] = &_ops,
4305
+#include <linux/bpf_types.h>
4306
+#undef BPF_PROG_TYPE
4307
+#undef BPF_LINK_TYPE
4308
+#undef BPF_MAP_TYPE
4309
+};
4310
+
4311
+static int btf_vmlinux_map_ids_init(const struct btf *btf,
4312
+ struct bpf_verifier_log *log)
4313
+{
4314
+ const struct bpf_map_ops *ops;
4315
+ int i, btf_id;
4316
+
4317
+ for (i = 0; i < ARRAY_SIZE(btf_vmlinux_map_ops); ++i) {
4318
+ ops = btf_vmlinux_map_ops[i];
4319
+ if (!ops || (!ops->map_btf_name && !ops->map_btf_id))
4320
+ continue;
4321
+ if (!ops->map_btf_name || !ops->map_btf_id) {
4322
+ bpf_log(log, "map type %d is misconfigured\n", i);
4323
+ return -EINVAL;
4324
+ }
4325
+ btf_id = btf_find_by_name_kind(btf, ops->map_btf_name,
4326
+ BTF_KIND_STRUCT);
4327
+ if (btf_id < 0)
4328
+ return btf_id;
4329
+ *ops->map_btf_id = btf_id;
4330
+ }
4331
+
4332
+ return 0;
4333
+}
4334
+
4335
+static int btf_translate_to_vmlinux(struct bpf_verifier_log *log,
4336
+ struct btf *btf,
4337
+ const struct btf_type *t,
4338
+ enum bpf_prog_type prog_type,
4339
+ int arg)
4340
+{
4341
+ const struct btf_member *prog_ctx_type, *kern_ctx_type;
4342
+
4343
+ prog_ctx_type = btf_get_prog_ctx_type(log, btf, t, prog_type, arg);
4344
+ if (!prog_ctx_type)
4345
+ return -ENOENT;
4346
+ kern_ctx_type = prog_ctx_type + 1;
4347
+ return kern_ctx_type->type;
4348
+}
4349
+
4350
+BTF_ID_LIST(bpf_ctx_convert_btf_id)
4351
+BTF_ID(struct, bpf_ctx_convert)
4352
+
4353
+struct btf *btf_parse_vmlinux(void)
4354
+{
4355
+ struct btf_verifier_env *env = NULL;
4356
+ struct bpf_verifier_log *log;
4357
+ struct btf *btf = NULL;
4358
+ int err;
4359
+
4360
+ env = kzalloc(sizeof(*env), GFP_KERNEL | __GFP_NOWARN);
4361
+ if (!env)
4362
+ return ERR_PTR(-ENOMEM);
4363
+
4364
+ log = &env->log;
4365
+ log->level = BPF_LOG_KERNEL;
4366
+
4367
+ btf = kzalloc(sizeof(*btf), GFP_KERNEL | __GFP_NOWARN);
4368
+ if (!btf) {
4369
+ err = -ENOMEM;
4370
+ goto errout;
4371
+ }
4372
+ env->btf = btf;
4373
+
4374
+ btf->data = __start_BTF;
4375
+ btf->data_size = __stop_BTF - __start_BTF;
4376
+
4377
+ err = btf_parse_hdr(env);
4378
+ if (err)
4379
+ goto errout;
4380
+
4381
+ btf->nohdr_data = btf->data + btf->hdr.hdr_len;
4382
+
4383
+ err = btf_parse_str_sec(env);
4384
+ if (err)
4385
+ goto errout;
4386
+
4387
+ err = btf_check_all_metas(env);
4388
+ if (err)
4389
+ goto errout;
4390
+
4391
+ /* btf_parse_vmlinux() runs under bpf_verifier_lock */
4392
+ bpf_ctx_convert.t = btf_type_by_id(btf, bpf_ctx_convert_btf_id[0]);
4393
+
4394
+ /* find bpf map structs for map_ptr access checking */
4395
+ err = btf_vmlinux_map_ids_init(btf, log);
4396
+ if (err < 0)
4397
+ goto errout;
4398
+
4399
+ bpf_struct_ops_init(btf, log);
4400
+
4401
+ btf_verifier_env_free(env);
4402
+ refcount_set(&btf->refcnt, 1);
4403
+ return btf;
4404
+
4405
+errout:
4406
+ btf_verifier_env_free(env);
4407
+ if (btf) {
4408
+ kvfree(btf->types);
4409
+ kfree(btf);
4410
+ }
4411
+ return ERR_PTR(err);
4412
+}
4413
+
4414
+struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog)
4415
+{
4416
+ struct bpf_prog *tgt_prog = prog->aux->dst_prog;
4417
+
4418
+ if (tgt_prog) {
4419
+ return tgt_prog->aux->btf;
4420
+ } else {
4421
+ return btf_vmlinux;
4422
+ }
4423
+}
4424
+
4425
+static bool is_string_ptr(struct btf *btf, const struct btf_type *t)
4426
+{
4427
+ /* t comes in already as a pointer */
4428
+ t = btf_type_by_id(btf, t->type);
4429
+
4430
+ /* allow const */
4431
+ if (BTF_INFO_KIND(t->info) == BTF_KIND_CONST)
4432
+ t = btf_type_by_id(btf, t->type);
4433
+
4434
+ /* char, signed char, unsigned char */
4435
+ return btf_type_is_int(t) && t->size == 1;
4436
+}
4437
+
4438
+bool btf_ctx_access(int off, int size, enum bpf_access_type type,
4439
+ const struct bpf_prog *prog,
4440
+ struct bpf_insn_access_aux *info)
4441
+{
4442
+ const struct btf_type *t = prog->aux->attach_func_proto;
4443
+ struct bpf_prog *tgt_prog = prog->aux->dst_prog;
4444
+ struct btf *btf = bpf_prog_get_target_btf(prog);
4445
+ const char *tname = prog->aux->attach_func_name;
4446
+ struct bpf_verifier_log *log = info->log;
4447
+ const struct btf_param *args;
4448
+ u32 nr_args, arg;
4449
+ int i, ret;
4450
+
4451
+ if (off % 8) {
4452
+ bpf_log(log, "func '%s' offset %d is not multiple of 8\n",
4453
+ tname, off);
4454
+ return false;
4455
+ }
4456
+ arg = off / 8;
4457
+ args = (const struct btf_param *)(t + 1);
4458
+ /* if (t == NULL) Fall back to default BPF prog with 5 u64 arguments */
4459
+ nr_args = t ? btf_type_vlen(t) : 5;
4460
+ if (prog->aux->attach_btf_trace) {
4461
+ /* skip first 'void *__data' argument in btf_trace_##name typedef */
4462
+ args++;
4463
+ nr_args--;
4464
+ }
4465
+
4466
+ if (arg > nr_args) {
4467
+ bpf_log(log, "func '%s' doesn't have %d-th argument\n",
4468
+ tname, arg + 1);
4469
+ return false;
4470
+ }
4471
+
4472
+ if (arg == nr_args) {
4473
+ switch (prog->expected_attach_type) {
4474
+ case BPF_LSM_MAC:
4475
+ case BPF_TRACE_FEXIT:
4476
+ /* When LSM programs are attached to void LSM hooks
4477
+ * they use FEXIT trampolines and when attached to
4478
+ * int LSM hooks, they use MODIFY_RETURN trampolines.
4479
+ *
4480
+ * While the LSM programs are BPF_MODIFY_RETURN-like
4481
+ * the check:
4482
+ *
4483
+ * if (ret_type != 'int')
4484
+ * return -EINVAL;
4485
+ *
4486
+ * is _not_ done here. This is still safe as LSM hooks
4487
+ * have only void and int return types.
4488
+ */
4489
+ if (!t)
4490
+ return true;
4491
+ t = btf_type_by_id(btf, t->type);
4492
+ break;
4493
+ case BPF_MODIFY_RETURN:
4494
+ /* For now the BPF_MODIFY_RETURN can only be attached to
4495
+ * functions that return an int.
4496
+ */
4497
+ if (!t)
4498
+ return false;
4499
+
4500
+ t = btf_type_skip_modifiers(btf, t->type, NULL);
4501
+ if (!btf_type_is_small_int(t)) {
4502
+ bpf_log(log,
4503
+ "ret type %s not allowed for fmod_ret\n",
4504
+ btf_kind_str[BTF_INFO_KIND(t->info)]);
4505
+ return false;
4506
+ }
4507
+ break;
4508
+ default:
4509
+ bpf_log(log, "func '%s' doesn't have %d-th argument\n",
4510
+ tname, arg + 1);
4511
+ return false;
4512
+ }
4513
+ } else {
4514
+ if (!t)
4515
+ /* Default prog with 5 args */
4516
+ return true;
4517
+ t = btf_type_by_id(btf, args[arg].type);
4518
+ }
4519
+
4520
+ /* skip modifiers */
4521
+ while (btf_type_is_modifier(t))
4522
+ t = btf_type_by_id(btf, t->type);
4523
+ if (btf_type_is_small_int(t) || btf_type_is_enum(t))
4524
+ /* accessing a scalar */
4525
+ return true;
4526
+ if (!btf_type_is_ptr(t)) {
4527
+ bpf_log(log,
4528
+ "func '%s' arg%d '%s' has type %s. Only pointer access is allowed\n",
4529
+ tname, arg,
4530
+ __btf_name_by_offset(btf, t->name_off),
4531
+ btf_kind_str[BTF_INFO_KIND(t->info)]);
4532
+ return false;
4533
+ }
4534
+
4535
+ /* check for PTR_TO_RDONLY_BUF_OR_NULL or PTR_TO_RDWR_BUF_OR_NULL */
4536
+ for (i = 0; i < prog->aux->ctx_arg_info_size; i++) {
4537
+ const struct bpf_ctx_arg_aux *ctx_arg_info = &prog->aux->ctx_arg_info[i];
4538
+
4539
+ if (ctx_arg_info->offset == off &&
4540
+ (ctx_arg_info->reg_type == PTR_TO_RDONLY_BUF_OR_NULL ||
4541
+ ctx_arg_info->reg_type == PTR_TO_RDWR_BUF_OR_NULL)) {
4542
+ info->reg_type = ctx_arg_info->reg_type;
4543
+ return true;
4544
+ }
4545
+ }
4546
+
4547
+ if (t->type == 0)
4548
+ /* This is a pointer to void.
4549
+ * It is the same as scalar from the verifier safety pov.
4550
+ * No further pointer walking is allowed.
4551
+ */
4552
+ return true;
4553
+
4554
+ if (is_string_ptr(btf, t))
4555
+ return true;
4556
+
4557
+ /* this is a pointer to another type */
4558
+ for (i = 0; i < prog->aux->ctx_arg_info_size; i++) {
4559
+ const struct bpf_ctx_arg_aux *ctx_arg_info = &prog->aux->ctx_arg_info[i];
4560
+
4561
+ if (ctx_arg_info->offset == off) {
4562
+ info->reg_type = ctx_arg_info->reg_type;
4563
+ info->btf_id = ctx_arg_info->btf_id;
4564
+ return true;
4565
+ }
4566
+ }
4567
+
4568
+ info->reg_type = PTR_TO_BTF_ID;
4569
+ if (tgt_prog) {
4570
+ enum bpf_prog_type tgt_type;
4571
+
4572
+ if (tgt_prog->type == BPF_PROG_TYPE_EXT)
4573
+ tgt_type = tgt_prog->aux->saved_dst_prog_type;
4574
+ else
4575
+ tgt_type = tgt_prog->type;
4576
+
4577
+ ret = btf_translate_to_vmlinux(log, btf, t, tgt_type, arg);
4578
+ if (ret > 0) {
4579
+ info->btf_id = ret;
4580
+ return true;
4581
+ } else {
4582
+ return false;
4583
+ }
4584
+ }
4585
+
4586
+ info->btf_id = t->type;
4587
+ t = btf_type_by_id(btf, t->type);
4588
+ /* skip modifiers */
4589
+ while (btf_type_is_modifier(t)) {
4590
+ info->btf_id = t->type;
4591
+ t = btf_type_by_id(btf, t->type);
4592
+ }
4593
+ if (!btf_type_is_struct(t)) {
4594
+ bpf_log(log,
4595
+ "func '%s' arg%d type %s is not a struct\n",
4596
+ tname, arg, btf_kind_str[BTF_INFO_KIND(t->info)]);
4597
+ return false;
4598
+ }
4599
+ bpf_log(log, "func '%s' arg%d has btf_id %d type %s '%s'\n",
4600
+ tname, arg, info->btf_id, btf_kind_str[BTF_INFO_KIND(t->info)],
4601
+ __btf_name_by_offset(btf, t->name_off));
4602
+ return true;
4603
+}
4604
+
4605
+enum bpf_struct_walk_result {
4606
+ /* < 0 error */
4607
+ WALK_SCALAR = 0,
4608
+ WALK_PTR,
4609
+ WALK_STRUCT,
4610
+};
4611
+
4612
+static int btf_struct_walk(struct bpf_verifier_log *log,
4613
+ const struct btf_type *t, int off, int size,
4614
+ u32 *next_btf_id)
4615
+{
4616
+ u32 i, moff, mtrue_end, msize = 0, total_nelems = 0;
4617
+ const struct btf_type *mtype, *elem_type = NULL;
4618
+ const struct btf_member *member;
4619
+ const char *tname, *mname;
4620
+ u32 vlen, elem_id, mid;
4621
+
4622
+again:
4623
+ tname = __btf_name_by_offset(btf_vmlinux, t->name_off);
4624
+ if (!btf_type_is_struct(t)) {
4625
+ bpf_log(log, "Type '%s' is not a struct\n", tname);
4626
+ return -EINVAL;
4627
+ }
4628
+
4629
+ vlen = btf_type_vlen(t);
4630
+ if (off + size > t->size) {
4631
+ /* If the last element is a variable size array, we may
4632
+ * need to relax the rule.
4633
+ */
4634
+ struct btf_array *array_elem;
4635
+
4636
+ if (vlen == 0)
4637
+ goto error;
4638
+
4639
+ member = btf_type_member(t) + vlen - 1;
4640
+ mtype = btf_type_skip_modifiers(btf_vmlinux, member->type,
4641
+ NULL);
4642
+ if (!btf_type_is_array(mtype))
4643
+ goto error;
4644
+
4645
+ array_elem = (struct btf_array *)(mtype + 1);
4646
+ if (array_elem->nelems != 0)
4647
+ goto error;
4648
+
4649
+ moff = btf_member_bit_offset(t, member) / 8;
4650
+ if (off < moff)
4651
+ goto error;
4652
+
4653
+ /* Only allow structure for now, can be relaxed for
4654
+ * other types later.
4655
+ */
4656
+ t = btf_type_skip_modifiers(btf_vmlinux, array_elem->type,
4657
+ NULL);
4658
+ if (!btf_type_is_struct(t))
4659
+ goto error;
4660
+
4661
+ off = (off - moff) % t->size;
4662
+ goto again;
4663
+
4664
+error:
4665
+ bpf_log(log, "access beyond struct %s at off %u size %u\n",
4666
+ tname, off, size);
4667
+ return -EACCES;
4668
+ }
4669
+
4670
+ for_each_member(i, t, member) {
4671
+ /* offset of the field in bytes */
4672
+ moff = btf_member_bit_offset(t, member) / 8;
4673
+ if (off + size <= moff)
4674
+ /* won't find anything, field is already too far */
4675
+ break;
4676
+
4677
+ if (btf_member_bitfield_size(t, member)) {
4678
+ u32 end_bit = btf_member_bit_offset(t, member) +
4679
+ btf_member_bitfield_size(t, member);
4680
+
4681
+ /* off <= moff instead of off == moff because clang
4682
+ * does not generate a BTF member for anonymous
4683
+ * bitfield like the ":16" here:
4684
+ * struct {
4685
+ * int :16;
4686
+ * int x:8;
4687
+ * };
4688
+ */
4689
+ if (off <= moff &&
4690
+ BITS_ROUNDUP_BYTES(end_bit) <= off + size)
4691
+ return WALK_SCALAR;
4692
+
4693
+ /* off may be accessing a following member
4694
+ *
4695
+ * or
4696
+ *
4697
+ * Doing partial access at either end of this
4698
+ * bitfield. Continue on this case also to
4699
+ * treat it as not accessing this bitfield
4700
+ * and eventually error out as field not
4701
+ * found to keep it simple.
4702
+ * It could be relaxed if there was a legit
4703
+ * partial access case later.
4704
+ */
4705
+ continue;
4706
+ }
4707
+
4708
+ /* In case of "off" is pointing to holes of a struct */
4709
+ if (off < moff)
4710
+ break;
4711
+
4712
+ /* type of the field */
4713
+ mid = member->type;
4714
+ mtype = btf_type_by_id(btf_vmlinux, member->type);
4715
+ mname = __btf_name_by_offset(btf_vmlinux, member->name_off);
4716
+
4717
+ mtype = __btf_resolve_size(btf_vmlinux, mtype, &msize,
4718
+ &elem_type, &elem_id, &total_nelems,
4719
+ &mid);
4720
+ if (IS_ERR(mtype)) {
4721
+ bpf_log(log, "field %s doesn't have size\n", mname);
4722
+ return -EFAULT;
4723
+ }
4724
+
4725
+ mtrue_end = moff + msize;
4726
+ if (off >= mtrue_end)
4727
+ /* no overlap with member, keep iterating */
4728
+ continue;
4729
+
4730
+ if (btf_type_is_array(mtype)) {
4731
+ u32 elem_idx;
4732
+
4733
+ /* __btf_resolve_size() above helps to
4734
+ * linearize a multi-dimensional array.
4735
+ *
4736
+ * The logic here is treating an array
4737
+ * in a struct as the following way:
4738
+ *
4739
+ * struct outer {
4740
+ * struct inner array[2][2];
4741
+ * };
4742
+ *
4743
+ * looks like:
4744
+ *
4745
+ * struct outer {
4746
+ * struct inner array_elem0;
4747
+ * struct inner array_elem1;
4748
+ * struct inner array_elem2;
4749
+ * struct inner array_elem3;
4750
+ * };
4751
+ *
4752
+ * When accessing outer->array[1][0], it moves
4753
+ * moff to "array_elem2", set mtype to
4754
+ * "struct inner", and msize also becomes
4755
+ * sizeof(struct inner). Then most of the
4756
+ * remaining logic will fall through without
4757
+ * caring the current member is an array or
4758
+ * not.
4759
+ *
4760
+ * Unlike mtype/msize/moff, mtrue_end does not
4761
+ * change. The naming difference ("_true") tells
4762
+ * that it is not always corresponding to
4763
+ * the current mtype/msize/moff.
4764
+ * It is the true end of the current
4765
+ * member (i.e. array in this case). That
4766
+ * will allow an int array to be accessed like
4767
+ * a scratch space,
4768
+ * i.e. allow access beyond the size of
4769
+ * the array's element as long as it is
4770
+ * within the mtrue_end boundary.
4771
+ */
4772
+
4773
+ /* skip empty array */
4774
+ if (moff == mtrue_end)
4775
+ continue;
4776
+
4777
+ msize /= total_nelems;
4778
+ elem_idx = (off - moff) / msize;
4779
+ moff += elem_idx * msize;
4780
+ mtype = elem_type;
4781
+ mid = elem_id;
4782
+ }
4783
+
4784
+ /* the 'off' we're looking for is either equal to start
4785
+ * of this field or inside of this struct
4786
+ */
4787
+ if (btf_type_is_struct(mtype)) {
4788
+ /* our field must be inside that union or struct */
4789
+ t = mtype;
4790
+
4791
+ /* return if the offset matches the member offset */
4792
+ if (off == moff) {
4793
+ *next_btf_id = mid;
4794
+ return WALK_STRUCT;
4795
+ }
4796
+
4797
+ /* adjust offset we're looking for */
4798
+ off -= moff;
4799
+ goto again;
4800
+ }
4801
+
4802
+ if (btf_type_is_ptr(mtype)) {
4803
+ const struct btf_type *stype;
4804
+ u32 id;
4805
+
4806
+ if (msize != size || off != moff) {
4807
+ bpf_log(log,
4808
+ "cannot access ptr member %s with moff %u in struct %s with off %u size %u\n",
4809
+ mname, moff, tname, off, size);
4810
+ return -EACCES;
4811
+ }
4812
+ stype = btf_type_skip_modifiers(btf_vmlinux, mtype->type, &id);
4813
+ if (btf_type_is_struct(stype)) {
4814
+ *next_btf_id = id;
4815
+ return WALK_PTR;
4816
+ }
4817
+ }
4818
+
4819
+ /* Allow more flexible access within an int as long as
4820
+ * it is within mtrue_end.
4821
+ * Since mtrue_end could be the end of an array,
4822
+ * that also allows using an array of int as a scratch
4823
+ * space. e.g. skb->cb[].
4824
+ */
4825
+ if (off + size > mtrue_end) {
4826
+ bpf_log(log,
4827
+ "access beyond the end of member %s (mend:%u) in struct %s with off %u size %u\n",
4828
+ mname, mtrue_end, tname, off, size);
4829
+ return -EACCES;
4830
+ }
4831
+
4832
+ return WALK_SCALAR;
4833
+ }
4834
+ bpf_log(log, "struct %s doesn't have field at offset %d\n", tname, off);
4835
+ return -EINVAL;
4836
+}
4837
+
4838
+int btf_struct_access(struct bpf_verifier_log *log,
4839
+ const struct btf_type *t, int off, int size,
4840
+ enum bpf_access_type atype __maybe_unused,
4841
+ u32 *next_btf_id)
4842
+{
4843
+ int err;
4844
+ u32 id;
4845
+
4846
+ do {
4847
+ err = btf_struct_walk(log, t, off, size, &id);
4848
+
4849
+ switch (err) {
4850
+ case WALK_PTR:
4851
+ /* If we found the pointer or scalar on t+off,
4852
+ * we're done.
4853
+ */
4854
+ *next_btf_id = id;
4855
+ return PTR_TO_BTF_ID;
4856
+ case WALK_SCALAR:
4857
+ return SCALAR_VALUE;
4858
+ case WALK_STRUCT:
4859
+ /* We found nested struct, so continue the search
4860
+ * by diving in it. At this point the offset is
4861
+ * aligned with the new type, so set it to 0.
4862
+ */
4863
+ t = btf_type_by_id(btf_vmlinux, id);
4864
+ off = 0;
4865
+ break;
4866
+ default:
4867
+ /* It's either error or unknown return value..
4868
+ * scream and leave.
4869
+ */
4870
+ if (WARN_ONCE(err > 0, "unknown btf_struct_walk return value"))
4871
+ return -EINVAL;
4872
+ return err;
4873
+ }
4874
+ } while (t);
4875
+
4876
+ return -EINVAL;
4877
+}
4878
+
4879
+bool btf_struct_ids_match(struct bpf_verifier_log *log,
4880
+ int off, u32 id, u32 need_type_id)
4881
+{
4882
+ const struct btf_type *type;
4883
+ int err;
4884
+
4885
+ /* Are we already done? */
4886
+ if (need_type_id == id && off == 0)
4887
+ return true;
4888
+
4889
+again:
4890
+ type = btf_type_by_id(btf_vmlinux, id);
4891
+ if (!type)
4892
+ return false;
4893
+ err = btf_struct_walk(log, type, off, 1, &id);
4894
+ if (err != WALK_STRUCT)
4895
+ return false;
4896
+
4897
+ /* We found nested struct object. If it matches
4898
+ * the requested ID, we're done. Otherwise let's
4899
+ * continue the search with offset 0 in the new
4900
+ * type.
4901
+ */
4902
+ if (need_type_id != id) {
4903
+ off = 0;
4904
+ goto again;
4905
+ }
4906
+
4907
+ return true;
4908
+}
4909
+
4910
+static int __get_type_size(struct btf *btf, u32 btf_id,
4911
+ const struct btf_type **bad_type)
4912
+{
4913
+ const struct btf_type *t;
4914
+
4915
+ if (!btf_id)
4916
+ /* void */
4917
+ return 0;
4918
+ t = btf_type_by_id(btf, btf_id);
4919
+ while (t && btf_type_is_modifier(t))
4920
+ t = btf_type_by_id(btf, t->type);
4921
+ if (!t) {
4922
+ *bad_type = btf->types[0];
4923
+ return -EINVAL;
4924
+ }
4925
+ if (btf_type_is_ptr(t))
4926
+ /* kernel size of pointer. Not BPF's size of pointer*/
4927
+ return sizeof(void *);
4928
+ if (btf_type_is_int(t) || btf_type_is_enum(t))
4929
+ return t->size;
4930
+ *bad_type = t;
4931
+ return -EINVAL;
4932
+}
4933
+
4934
+int btf_distill_func_proto(struct bpf_verifier_log *log,
4935
+ struct btf *btf,
4936
+ const struct btf_type *func,
4937
+ const char *tname,
4938
+ struct btf_func_model *m)
4939
+{
4940
+ const struct btf_param *args;
4941
+ const struct btf_type *t;
4942
+ u32 i, nargs;
4943
+ int ret;
4944
+
4945
+ if (!func) {
4946
+ /* BTF function prototype doesn't match the verifier types.
4947
+ * Fall back to 5 u64 args.
4948
+ */
4949
+ for (i = 0; i < 5; i++)
4950
+ m->arg_size[i] = 8;
4951
+ m->ret_size = 8;
4952
+ m->nr_args = 5;
4953
+ return 0;
4954
+ }
4955
+ args = (const struct btf_param *)(func + 1);
4956
+ nargs = btf_type_vlen(func);
4957
+ if (nargs >= MAX_BPF_FUNC_ARGS) {
4958
+ bpf_log(log,
4959
+ "The function %s has %d arguments. Too many.\n",
4960
+ tname, nargs);
4961
+ return -EINVAL;
4962
+ }
4963
+ ret = __get_type_size(btf, func->type, &t);
4964
+ if (ret < 0) {
4965
+ bpf_log(log,
4966
+ "The function %s return type %s is unsupported.\n",
4967
+ tname, btf_kind_str[BTF_INFO_KIND(t->info)]);
4968
+ return -EINVAL;
4969
+ }
4970
+ m->ret_size = ret;
4971
+
4972
+ for (i = 0; i < nargs; i++) {
4973
+ if (i == nargs - 1 && args[i].type == 0) {
4974
+ bpf_log(log,
4975
+ "The function %s with variable args is unsupported.\n",
4976
+ tname);
4977
+ return -EINVAL;
4978
+ }
4979
+ ret = __get_type_size(btf, args[i].type, &t);
4980
+ if (ret < 0) {
4981
+ bpf_log(log,
4982
+ "The function %s arg%d type %s is unsupported.\n",
4983
+ tname, i, btf_kind_str[BTF_INFO_KIND(t->info)]);
4984
+ return -EINVAL;
4985
+ }
4986
+ if (ret == 0) {
4987
+ bpf_log(log,
4988
+ "The function %s has malformed void argument.\n",
4989
+ tname);
4990
+ return -EINVAL;
4991
+ }
4992
+ m->arg_size[i] = ret;
4993
+ }
4994
+ m->nr_args = nargs;
4995
+ return 0;
4996
+}
4997
+
4998
+/* Compare BTFs of two functions assuming only scalars and pointers to context.
4999
+ * t1 points to BTF_KIND_FUNC in btf1
5000
+ * t2 points to BTF_KIND_FUNC in btf2
5001
+ * Returns:
5002
+ * EINVAL - function prototype mismatch
5003
+ * EFAULT - verifier bug
5004
+ * 0 - 99% match. The last 1% is validated by the verifier.
5005
+ */
5006
+static int btf_check_func_type_match(struct bpf_verifier_log *log,
5007
+ struct btf *btf1, const struct btf_type *t1,
5008
+ struct btf *btf2, const struct btf_type *t2)
5009
+{
5010
+ const struct btf_param *args1, *args2;
5011
+ const char *fn1, *fn2, *s1, *s2;
5012
+ u32 nargs1, nargs2, i;
5013
+
5014
+ fn1 = btf_name_by_offset(btf1, t1->name_off);
5015
+ fn2 = btf_name_by_offset(btf2, t2->name_off);
5016
+
5017
+ if (btf_func_linkage(t1) != BTF_FUNC_GLOBAL) {
5018
+ bpf_log(log, "%s() is not a global function\n", fn1);
5019
+ return -EINVAL;
5020
+ }
5021
+ if (btf_func_linkage(t2) != BTF_FUNC_GLOBAL) {
5022
+ bpf_log(log, "%s() is not a global function\n", fn2);
5023
+ return -EINVAL;
5024
+ }
5025
+
5026
+ t1 = btf_type_by_id(btf1, t1->type);
5027
+ if (!t1 || !btf_type_is_func_proto(t1))
5028
+ return -EFAULT;
5029
+ t2 = btf_type_by_id(btf2, t2->type);
5030
+ if (!t2 || !btf_type_is_func_proto(t2))
5031
+ return -EFAULT;
5032
+
5033
+ args1 = (const struct btf_param *)(t1 + 1);
5034
+ nargs1 = btf_type_vlen(t1);
5035
+ args2 = (const struct btf_param *)(t2 + 1);
5036
+ nargs2 = btf_type_vlen(t2);
5037
+
5038
+ if (nargs1 != nargs2) {
5039
+ bpf_log(log, "%s() has %d args while %s() has %d args\n",
5040
+ fn1, nargs1, fn2, nargs2);
5041
+ return -EINVAL;
5042
+ }
5043
+
5044
+ t1 = btf_type_skip_modifiers(btf1, t1->type, NULL);
5045
+ t2 = btf_type_skip_modifiers(btf2, t2->type, NULL);
5046
+ if (t1->info != t2->info) {
5047
+ bpf_log(log,
5048
+ "Return type %s of %s() doesn't match type %s of %s()\n",
5049
+ btf_type_str(t1), fn1,
5050
+ btf_type_str(t2), fn2);
5051
+ return -EINVAL;
5052
+ }
5053
+
5054
+ for (i = 0; i < nargs1; i++) {
5055
+ t1 = btf_type_skip_modifiers(btf1, args1[i].type, NULL);
5056
+ t2 = btf_type_skip_modifiers(btf2, args2[i].type, NULL);
5057
+
5058
+ if (t1->info != t2->info) {
5059
+ bpf_log(log, "arg%d in %s() is %s while %s() has %s\n",
5060
+ i, fn1, btf_type_str(t1),
5061
+ fn2, btf_type_str(t2));
5062
+ return -EINVAL;
5063
+ }
5064
+ if (btf_type_has_size(t1) && t1->size != t2->size) {
5065
+ bpf_log(log,
5066
+ "arg%d in %s() has size %d while %s() has %d\n",
5067
+ i, fn1, t1->size,
5068
+ fn2, t2->size);
5069
+ return -EINVAL;
5070
+ }
5071
+
5072
+ /* global functions are validated with scalars and pointers
5073
+ * to context only. And only global functions can be replaced.
5074
+ * Hence type check only those types.
5075
+ */
5076
+ if (btf_type_is_int(t1) || btf_type_is_enum(t1))
5077
+ continue;
5078
+ if (!btf_type_is_ptr(t1)) {
5079
+ bpf_log(log,
5080
+ "arg%d in %s() has unrecognized type\n",
5081
+ i, fn1);
5082
+ return -EINVAL;
5083
+ }
5084
+ t1 = btf_type_skip_modifiers(btf1, t1->type, NULL);
5085
+ t2 = btf_type_skip_modifiers(btf2, t2->type, NULL);
5086
+ if (!btf_type_is_struct(t1)) {
5087
+ bpf_log(log,
5088
+ "arg%d in %s() is not a pointer to context\n",
5089
+ i, fn1);
5090
+ return -EINVAL;
5091
+ }
5092
+ if (!btf_type_is_struct(t2)) {
5093
+ bpf_log(log,
5094
+ "arg%d in %s() is not a pointer to context\n",
5095
+ i, fn2);
5096
+ return -EINVAL;
5097
+ }
5098
+ /* This is an optional check to make program writing easier.
5099
+ * Compare names of structs and report an error to the user.
5100
+ * btf_prepare_func_args() already checked that t2 struct
5101
+ * is a context type. btf_prepare_func_args() will check
5102
+ * later that t1 struct is a context type as well.
5103
+ */
5104
+ s1 = btf_name_by_offset(btf1, t1->name_off);
5105
+ s2 = btf_name_by_offset(btf2, t2->name_off);
5106
+ if (strcmp(s1, s2)) {
5107
+ bpf_log(log,
5108
+ "arg%d %s(struct %s *) doesn't match %s(struct %s *)\n",
5109
+ i, fn1, s1, fn2, s2);
5110
+ return -EINVAL;
5111
+ }
5112
+ }
5113
+ return 0;
5114
+}
5115
+
5116
+/* Compare BTFs of given program with BTF of target program */
5117
+int btf_check_type_match(struct bpf_verifier_log *log, const struct bpf_prog *prog,
5118
+ struct btf *btf2, const struct btf_type *t2)
5119
+{
5120
+ struct btf *btf1 = prog->aux->btf;
5121
+ const struct btf_type *t1;
5122
+ u32 btf_id = 0;
5123
+
5124
+ if (!prog->aux->func_info) {
5125
+ bpf_log(log, "Program extension requires BTF\n");
5126
+ return -EINVAL;
5127
+ }
5128
+
5129
+ btf_id = prog->aux->func_info[0].type_id;
5130
+ if (!btf_id)
5131
+ return -EFAULT;
5132
+
5133
+ t1 = btf_type_by_id(btf1, btf_id);
5134
+ if (!t1 || !btf_type_is_func(t1))
5135
+ return -EFAULT;
5136
+
5137
+ return btf_check_func_type_match(log, btf1, t1, btf2, t2);
5138
+}
5139
+
5140
+/* Compare BTF of a function with given bpf_reg_state.
5141
+ * Returns:
5142
+ * EFAULT - there is a verifier bug. Abort verification.
5143
+ * EINVAL - there is a type mismatch or BTF is not available.
5144
+ * 0 - BTF matches with what bpf_reg_state expects.
5145
+ * Only PTR_TO_CTX and SCALAR_VALUE states are recognized.
5146
+ */
5147
+int btf_check_func_arg_match(struct bpf_verifier_env *env, int subprog,
5148
+ struct bpf_reg_state *reg)
5149
+{
5150
+ struct bpf_verifier_log *log = &env->log;
5151
+ struct bpf_prog *prog = env->prog;
5152
+ struct btf *btf = prog->aux->btf;
5153
+ const struct btf_param *args;
5154
+ const struct btf_type *t;
5155
+ u32 i, nargs, btf_id;
5156
+ const char *tname;
5157
+
5158
+ if (!prog->aux->func_info)
5159
+ return -EINVAL;
5160
+
5161
+ btf_id = prog->aux->func_info[subprog].type_id;
5162
+ if (!btf_id)
5163
+ return -EFAULT;
5164
+
5165
+ if (prog->aux->func_info_aux[subprog].unreliable)
5166
+ return -EINVAL;
5167
+
5168
+ t = btf_type_by_id(btf, btf_id);
5169
+ if (!t || !btf_type_is_func(t)) {
5170
+ /* These checks were already done by the verifier while loading
5171
+ * struct bpf_func_info
5172
+ */
5173
+ bpf_log(log, "BTF of func#%d doesn't point to KIND_FUNC\n",
5174
+ subprog);
5175
+ return -EFAULT;
5176
+ }
5177
+ tname = btf_name_by_offset(btf, t->name_off);
5178
+
5179
+ t = btf_type_by_id(btf, t->type);
5180
+ if (!t || !btf_type_is_func_proto(t)) {
5181
+ bpf_log(log, "Invalid BTF of func %s\n", tname);
5182
+ return -EFAULT;
5183
+ }
5184
+ args = (const struct btf_param *)(t + 1);
5185
+ nargs = btf_type_vlen(t);
5186
+ if (nargs > 5) {
5187
+ bpf_log(log, "Function %s has %d > 5 args\n", tname, nargs);
5188
+ goto out;
5189
+ }
5190
+ /* check that BTF function arguments match actual types that the
5191
+ * verifier sees.
5192
+ */
5193
+ for (i = 0; i < nargs; i++) {
5194
+ t = btf_type_by_id(btf, args[i].type);
5195
+ while (btf_type_is_modifier(t))
5196
+ t = btf_type_by_id(btf, t->type);
5197
+ if (btf_type_is_int(t) || btf_type_is_enum(t)) {
5198
+ if (reg[i + 1].type == SCALAR_VALUE)
5199
+ continue;
5200
+ bpf_log(log, "R%d is not a scalar\n", i + 1);
5201
+ goto out;
5202
+ }
5203
+ if (btf_type_is_ptr(t)) {
5204
+ if (reg[i + 1].type == SCALAR_VALUE) {
5205
+ bpf_log(log, "R%d is not a pointer\n", i + 1);
5206
+ goto out;
5207
+ }
5208
+ /* If function expects ctx type in BTF check that caller
5209
+ * is passing PTR_TO_CTX.
5210
+ */
5211
+ if (btf_get_prog_ctx_type(log, btf, t, prog->type, i)) {
5212
+ if (reg[i + 1].type != PTR_TO_CTX) {
5213
+ bpf_log(log,
5214
+ "arg#%d expected pointer to ctx, but got %s\n",
5215
+ i, btf_kind_str[BTF_INFO_KIND(t->info)]);
5216
+ goto out;
5217
+ }
5218
+ if (check_ctx_reg(env, &reg[i + 1], i + 1))
5219
+ goto out;
5220
+ continue;
5221
+ }
5222
+ }
5223
+ bpf_log(log, "Unrecognized arg#%d type %s\n",
5224
+ i, btf_kind_str[BTF_INFO_KIND(t->info)]);
5225
+ goto out;
5226
+ }
5227
+ return 0;
5228
+out:
5229
+ /* Compiler optimizations can remove arguments from static functions
5230
+ * or mismatched type can be passed into a global function.
5231
+ * In such cases mark the function as unreliable from BTF point of view.
5232
+ */
5233
+ prog->aux->func_info_aux[subprog].unreliable = true;
5234
+ return -EINVAL;
5235
+}
5236
+
5237
+/* Convert BTF of a function into bpf_reg_state if possible
5238
+ * Returns:
5239
+ * EFAULT - there is a verifier bug. Abort verification.
5240
+ * EINVAL - cannot convert BTF.
5241
+ * 0 - Successfully converted BTF into bpf_reg_state
5242
+ * (either PTR_TO_CTX or SCALAR_VALUE).
5243
+ */
5244
+int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog,
5245
+ struct bpf_reg_state *reg)
5246
+{
5247
+ struct bpf_verifier_log *log = &env->log;
5248
+ struct bpf_prog *prog = env->prog;
5249
+ enum bpf_prog_type prog_type = prog->type;
5250
+ struct btf *btf = prog->aux->btf;
5251
+ const struct btf_param *args;
5252
+ const struct btf_type *t;
5253
+ u32 i, nargs, btf_id;
5254
+ const char *tname;
5255
+
5256
+ if (!prog->aux->func_info ||
5257
+ prog->aux->func_info_aux[subprog].linkage != BTF_FUNC_GLOBAL) {
5258
+ bpf_log(log, "Verifier bug\n");
5259
+ return -EFAULT;
5260
+ }
5261
+
5262
+ btf_id = prog->aux->func_info[subprog].type_id;
5263
+ if (!btf_id) {
5264
+ bpf_log(log, "Global functions need valid BTF\n");
5265
+ return -EFAULT;
5266
+ }
5267
+
5268
+ t = btf_type_by_id(btf, btf_id);
5269
+ if (!t || !btf_type_is_func(t)) {
5270
+ /* These checks were already done by the verifier while loading
5271
+ * struct bpf_func_info
5272
+ */
5273
+ bpf_log(log, "BTF of func#%d doesn't point to KIND_FUNC\n",
5274
+ subprog);
5275
+ return -EFAULT;
5276
+ }
5277
+ tname = btf_name_by_offset(btf, t->name_off);
5278
+
5279
+ if (log->level & BPF_LOG_LEVEL)
5280
+ bpf_log(log, "Validating %s() func#%d...\n",
5281
+ tname, subprog);
5282
+
5283
+ if (prog->aux->func_info_aux[subprog].unreliable) {
5284
+ bpf_log(log, "Verifier bug in function %s()\n", tname);
5285
+ return -EFAULT;
5286
+ }
5287
+ if (prog_type == BPF_PROG_TYPE_EXT)
5288
+ prog_type = prog->aux->dst_prog->type;
5289
+
5290
+ t = btf_type_by_id(btf, t->type);
5291
+ if (!t || !btf_type_is_func_proto(t)) {
5292
+ bpf_log(log, "Invalid type of function %s()\n", tname);
5293
+ return -EFAULT;
5294
+ }
5295
+ args = (const struct btf_param *)(t + 1);
5296
+ nargs = btf_type_vlen(t);
5297
+ if (nargs > 5) {
5298
+ bpf_log(log, "Global function %s() with %d > 5 args. Buggy compiler.\n",
5299
+ tname, nargs);
5300
+ return -EINVAL;
5301
+ }
5302
+ /* check that function returns int */
5303
+ t = btf_type_by_id(btf, t->type);
5304
+ while (btf_type_is_modifier(t))
5305
+ t = btf_type_by_id(btf, t->type);
5306
+ if (!btf_type_is_int(t) && !btf_type_is_enum(t)) {
5307
+ bpf_log(log,
5308
+ "Global function %s() doesn't return scalar. Only those are supported.\n",
5309
+ tname);
5310
+ return -EINVAL;
5311
+ }
5312
+ /* Convert BTF function arguments into verifier types.
5313
+ * Only PTR_TO_CTX and SCALAR are supported atm.
5314
+ */
5315
+ for (i = 0; i < nargs; i++) {
5316
+ t = btf_type_by_id(btf, args[i].type);
5317
+ while (btf_type_is_modifier(t))
5318
+ t = btf_type_by_id(btf, t->type);
5319
+ if (btf_type_is_int(t) || btf_type_is_enum(t)) {
5320
+ reg[i + 1].type = SCALAR_VALUE;
5321
+ continue;
5322
+ }
5323
+ if (btf_type_is_ptr(t) &&
5324
+ btf_get_prog_ctx_type(log, btf, t, prog_type, i)) {
5325
+ reg[i + 1].type = PTR_TO_CTX;
5326
+ continue;
5327
+ }
5328
+ bpf_log(log, "Arg#%d type %s in %s() is not supported yet.\n",
5329
+ i, btf_kind_str[BTF_INFO_KIND(t->info)], tname);
5330
+ return -EINVAL;
5331
+ }
5332
+ return 0;
5333
+}
5334
+
5335
+static void btf_type_show(const struct btf *btf, u32 type_id, void *obj,
5336
+ struct btf_show *show)
23115337 {
23125338 const struct btf_type *t = btf_type_by_id(btf, type_id);
23135339
2314
- btf_type_ops(t)->seq_show(btf, t, type_id, obj, 0, m);
5340
+ show->btf = btf;
5341
+ memset(&show->state, 0, sizeof(show->state));
5342
+ memset(&show->obj, 0, sizeof(show->obj));
5343
+
5344
+ btf_type_ops(t)->show(btf, t, type_id, obj, 0, show);
23155345 }
5346
+
5347
+static void btf_seq_show(struct btf_show *show, const char *fmt,
5348
+ va_list args)
5349
+{
5350
+ seq_vprintf((struct seq_file *)show->target, fmt, args);
5351
+}
5352
+
5353
+int btf_type_seq_show_flags(const struct btf *btf, u32 type_id,
5354
+ void *obj, struct seq_file *m, u64 flags)
5355
+{
5356
+ struct btf_show sseq;
5357
+
5358
+ sseq.target = m;
5359
+ sseq.showfn = btf_seq_show;
5360
+ sseq.flags = flags;
5361
+
5362
+ btf_type_show(btf, type_id, obj, &sseq);
5363
+
5364
+ return sseq.state.status;
5365
+}
5366
+
5367
+void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj,
5368
+ struct seq_file *m)
5369
+{
5370
+ (void) btf_type_seq_show_flags(btf, type_id, obj, m,
5371
+ BTF_SHOW_NONAME | BTF_SHOW_COMPACT |
5372
+ BTF_SHOW_ZERO | BTF_SHOW_UNSAFE);
5373
+}
5374
+
5375
+struct btf_show_snprintf {
5376
+ struct btf_show show;
5377
+ int len_left; /* space left in string */
5378
+ int len; /* length we would have written */
5379
+};
5380
+
5381
+static void btf_snprintf_show(struct btf_show *show, const char *fmt,
5382
+ va_list args)
5383
+{
5384
+ struct btf_show_snprintf *ssnprintf = (struct btf_show_snprintf *)show;
5385
+ int len;
5386
+
5387
+ len = vsnprintf(show->target, ssnprintf->len_left, fmt, args);
5388
+
5389
+ if (len < 0) {
5390
+ ssnprintf->len_left = 0;
5391
+ ssnprintf->len = len;
5392
+ } else if (len > ssnprintf->len_left) {
5393
+ /* no space, drive on to get length we would have written */
5394
+ ssnprintf->len_left = 0;
5395
+ ssnprintf->len += len;
5396
+ } else {
5397
+ ssnprintf->len_left -= len;
5398
+ ssnprintf->len += len;
5399
+ show->target += len;
5400
+ }
5401
+}
5402
+
5403
+int btf_type_snprintf_show(const struct btf *btf, u32 type_id, void *obj,
5404
+ char *buf, int len, u64 flags)
5405
+{
5406
+ struct btf_show_snprintf ssnprintf;
5407
+
5408
+ ssnprintf.show.target = buf;
5409
+ ssnprintf.show.flags = flags;
5410
+ ssnprintf.show.showfn = btf_snprintf_show;
5411
+ ssnprintf.len_left = len;
5412
+ ssnprintf.len = 0;
5413
+
5414
+ btf_type_show(btf, type_id, obj, (struct btf_show *)&ssnprintf);
5415
+
5416
+ /* If we encontered an error, return it. */
5417
+ if (ssnprintf.show.state.status)
5418
+ return ssnprintf.show.state.status;
5419
+
5420
+ /* Otherwise return length we would have written */
5421
+ return ssnprintf.len;
5422
+}
5423
+
5424
+#ifdef CONFIG_PROC_FS
5425
+static void bpf_btf_show_fdinfo(struct seq_file *m, struct file *filp)
5426
+{
5427
+ const struct btf *btf = filp->private_data;
5428
+
5429
+ seq_printf(m, "btf_id:\t%u\n", btf->id);
5430
+}
5431
+#endif
23165432
23175433 static int btf_release(struct inode *inode, struct file *filp)
23185434 {
....@@ -2321,6 +5437,9 @@
23215437 }
23225438
23235439 const struct file_operations btf_fops = {
5440
+#ifdef CONFIG_PROC_FS
5441
+ .show_fdinfo = bpf_btf_show_fdinfo,
5442
+#endif
23245443 .release = btf_release,
23255444 };
23265445
....@@ -2439,3 +5558,15 @@
24395558 {
24405559 return btf->id;
24415560 }
5561
+
5562
+static int btf_id_cmp_func(const void *a, const void *b)
5563
+{
5564
+ const int *pa = a, *pb = b;
5565
+
5566
+ return *pa - *pb;
5567
+}
5568
+
5569
+bool btf_id_set_contains(const struct btf_id_set *set, u32 id)
5570
+{
5571
+ return bsearch(&id, set->ids, set->cnt, sizeof(u32), btf_id_cmp_func) != NULL;
5572
+}