| .. | .. |
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| 7 | 7 | * |
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| 8 | 8 | * Some code borrowed from https://github.com/xairy/kasan-prototype by |
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| 9 | 9 | * Andrey Konovalov <andreyknvl@gmail.com> |
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| 10 | | - * |
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| 11 | | - * This program is free software; you can redistribute it and/or modify |
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| 12 | | - * it under the terms of the GNU General Public License version 2 as |
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| 13 | | - * published by the Free Software Foundation. |
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| 14 | | - * |
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| 15 | 10 | */ |
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| 16 | | - |
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| 17 | | -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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| 18 | | -#define DISABLE_BRANCH_PROFILING |
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| 19 | 11 | |
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| 20 | 12 | #include <linux/export.h> |
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| 21 | 13 | #include <linux/interrupt.h> |
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| 22 | 14 | #include <linux/init.h> |
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| 23 | 15 | #include <linux/kasan.h> |
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| 24 | 16 | #include <linux/kernel.h> |
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| 17 | +#include <linux/kfence.h> |
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| 25 | 18 | #include <linux/kmemleak.h> |
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| 26 | 19 | #include <linux/linkage.h> |
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| 27 | 20 | #include <linux/memblock.h> |
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| .. | .. |
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| 52 | 45 | s8 shadow_value = *(s8 *)kasan_mem_to_shadow((void *)addr); |
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| 53 | 46 | |
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| 54 | 47 | if (unlikely(shadow_value)) { |
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| 55 | | - s8 last_accessible_byte = addr & KASAN_SHADOW_MASK; |
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| 48 | + s8 last_accessible_byte = addr & KASAN_GRANULE_MASK; |
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| 56 | 49 | return unlikely(last_accessible_byte >= shadow_value); |
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| 57 | 50 | } |
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| 58 | 51 | |
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| .. | .. |
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| 68 | 61 | * Access crosses 8(shadow size)-byte boundary. Such access maps |
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| 69 | 62 | * into 2 shadow bytes, so we need to check them both. |
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| 70 | 63 | */ |
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| 71 | | - if (unlikely(((addr + size - 1) & KASAN_SHADOW_MASK) < size - 1)) |
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| 64 | + if (unlikely(((addr + size - 1) & KASAN_GRANULE_MASK) < size - 1)) |
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| 72 | 65 | return *shadow_addr || memory_is_poisoned_1(addr + size - 1); |
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| 73 | 66 | |
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| 74 | 67 | return memory_is_poisoned_1(addr + size - 1); |
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| .. | .. |
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| 79 | 72 | u16 *shadow_addr = (u16 *)kasan_mem_to_shadow((void *)addr); |
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| 80 | 73 | |
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| 81 | 74 | /* Unaligned 16-bytes access maps into 3 shadow bytes. */ |
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| 82 | | - if (unlikely(!IS_ALIGNED(addr, KASAN_SHADOW_SCALE_SIZE))) |
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| 75 | + if (unlikely(!IS_ALIGNED(addr, KASAN_GRANULE_SIZE))) |
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| 83 | 76 | return *shadow_addr || memory_is_poisoned_1(addr + 15); |
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| 84 | 77 | |
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| 85 | 78 | return *shadow_addr; |
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| .. | .. |
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| 140 | 133 | s8 *last_shadow = (s8 *)kasan_mem_to_shadow((void *)last_byte); |
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| 141 | 134 | |
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| 142 | 135 | if (unlikely(ret != (unsigned long)last_shadow || |
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| 143 | | - ((long)(last_byte & KASAN_SHADOW_MASK) >= *last_shadow))) |
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| 136 | + ((long)(last_byte & KASAN_GRANULE_MASK) >= *last_shadow))) |
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| 144 | 137 | return true; |
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| 145 | 138 | } |
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| 146 | 139 | return false; |
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| .. | .. |
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| 166 | 159 | return memory_is_poisoned_n(addr, size); |
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| 167 | 160 | } |
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| 168 | 161 | |
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| 169 | | -static __always_inline void check_memory_region_inline(unsigned long addr, |
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| 162 | +static __always_inline bool check_region_inline(unsigned long addr, |
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| 170 | 163 | size_t size, bool write, |
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| 171 | 164 | unsigned long ret_ip) |
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| 172 | 165 | { |
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| 173 | 166 | if (unlikely(size == 0)) |
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| 174 | | - return; |
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| 167 | + return true; |
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| 168 | + |
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| 169 | + if (unlikely(addr + size < addr)) |
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| 170 | + return !kasan_report(addr, size, write, ret_ip); |
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| 175 | 171 | |
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| 176 | 172 | if (unlikely((void *)addr < |
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| 177 | 173 | kasan_shadow_to_mem((void *)KASAN_SHADOW_START))) { |
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| 178 | | - kasan_report(addr, size, write, ret_ip); |
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| 179 | | - return; |
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| 174 | + return !kasan_report(addr, size, write, ret_ip); |
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| 180 | 175 | } |
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| 181 | 176 | |
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| 182 | 177 | if (likely(!memory_is_poisoned(addr, size))) |
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| 183 | | - return; |
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| 178 | + return true; |
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| 184 | 179 | |
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| 185 | | - kasan_report(addr, size, write, ret_ip); |
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| 180 | + return !kasan_report(addr, size, write, ret_ip); |
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| 186 | 181 | } |
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| 187 | 182 | |
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| 188 | | -void check_memory_region(unsigned long addr, size_t size, bool write, |
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| 189 | | - unsigned long ret_ip) |
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| 183 | +bool kasan_check_range(unsigned long addr, size_t size, bool write, |
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| 184 | + unsigned long ret_ip) |
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| 190 | 185 | { |
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| 191 | | - check_memory_region_inline(addr, size, write, ret_ip); |
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| 186 | + return check_region_inline(addr, size, write, ret_ip); |
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| 187 | +} |
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| 188 | + |
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| 189 | +bool kasan_byte_accessible(const void *addr) |
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| 190 | +{ |
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| 191 | + s8 shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(addr)); |
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| 192 | + |
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| 193 | + return shadow_byte >= 0 && shadow_byte < KASAN_GRANULE_SIZE; |
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| 192 | 194 | } |
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| 193 | 195 | |
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| 194 | 196 | void kasan_cache_shrink(struct kmem_cache *cache) |
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| 195 | 197 | { |
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| 196 | | - quarantine_remove_cache(cache); |
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| 198 | + kasan_quarantine_remove_cache(cache); |
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| 197 | 199 | } |
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| 198 | 200 | |
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| 199 | 201 | void kasan_cache_shutdown(struct kmem_cache *cache) |
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| 200 | 202 | { |
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| 201 | 203 | if (!__kmem_cache_empty(cache)) |
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| 202 | | - quarantine_remove_cache(cache); |
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| 204 | + kasan_quarantine_remove_cache(cache); |
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| 203 | 205 | } |
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| 204 | 206 | |
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| 205 | 207 | static void register_global(struct kasan_global *global) |
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| 206 | 208 | { |
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| 207 | | - size_t aligned_size = round_up(global->size, KASAN_SHADOW_SCALE_SIZE); |
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| 209 | + size_t aligned_size = round_up(global->size, KASAN_GRANULE_SIZE); |
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| 208 | 210 | |
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| 209 | | - kasan_unpoison_shadow(global->beg, global->size); |
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| 211 | + kasan_unpoison(global->beg, global->size, false); |
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| 210 | 212 | |
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| 211 | | - kasan_poison_shadow(global->beg + aligned_size, |
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| 212 | | - global->size_with_redzone - aligned_size, |
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| 213 | | - KASAN_GLOBAL_REDZONE); |
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| 213 | + kasan_poison(global->beg + aligned_size, |
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| 214 | + global->size_with_redzone - aligned_size, |
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| 215 | + KASAN_GLOBAL_REDZONE, false); |
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| 214 | 216 | } |
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| 215 | 217 | |
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| 216 | 218 | void __asan_register_globals(struct kasan_global *globals, size_t size) |
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| .. | .. |
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| 230 | 232 | #define DEFINE_ASAN_LOAD_STORE(size) \ |
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| 231 | 233 | void __asan_load##size(unsigned long addr) \ |
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| 232 | 234 | { \ |
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| 233 | | - check_memory_region_inline(addr, size, false, _RET_IP_);\ |
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| 235 | + check_region_inline(addr, size, false, _RET_IP_); \ |
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| 234 | 236 | } \ |
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| 235 | 237 | EXPORT_SYMBOL(__asan_load##size); \ |
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| 236 | 238 | __alias(__asan_load##size) \ |
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| .. | .. |
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| 238 | 240 | EXPORT_SYMBOL(__asan_load##size##_noabort); \ |
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| 239 | 241 | void __asan_store##size(unsigned long addr) \ |
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| 240 | 242 | { \ |
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| 241 | | - check_memory_region_inline(addr, size, true, _RET_IP_); \ |
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| 243 | + check_region_inline(addr, size, true, _RET_IP_); \ |
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| 242 | 244 | } \ |
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| 243 | 245 | EXPORT_SYMBOL(__asan_store##size); \ |
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| 244 | 246 | __alias(__asan_store##size) \ |
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| .. | .. |
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| 253 | 255 | |
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| 254 | 256 | void __asan_loadN(unsigned long addr, size_t size) |
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| 255 | 257 | { |
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| 256 | | - check_memory_region(addr, size, false, _RET_IP_); |
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| 258 | + kasan_check_range(addr, size, false, _RET_IP_); |
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| 257 | 259 | } |
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| 258 | 260 | EXPORT_SYMBOL(__asan_loadN); |
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| 259 | 261 | |
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| .. | .. |
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| 263 | 265 | |
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| 264 | 266 | void __asan_storeN(unsigned long addr, size_t size) |
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| 265 | 267 | { |
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| 266 | | - check_memory_region(addr, size, true, _RET_IP_); |
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| 268 | + kasan_check_range(addr, size, true, _RET_IP_); |
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| 267 | 269 | } |
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| 268 | 270 | EXPORT_SYMBOL(__asan_storeN); |
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| 269 | 271 | |
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| .. | .. |
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| 278 | 280 | /* Emitted by compiler to poison alloca()ed objects. */ |
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| 279 | 281 | void __asan_alloca_poison(unsigned long addr, size_t size) |
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| 280 | 282 | { |
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| 281 | | - size_t rounded_up_size = round_up(size, KASAN_SHADOW_SCALE_SIZE); |
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| 283 | + size_t rounded_up_size = round_up(size, KASAN_GRANULE_SIZE); |
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| 282 | 284 | size_t padding_size = round_up(size, KASAN_ALLOCA_REDZONE_SIZE) - |
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| 283 | 285 | rounded_up_size; |
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| 284 | | - size_t rounded_down_size = round_down(size, KASAN_SHADOW_SCALE_SIZE); |
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| 286 | + size_t rounded_down_size = round_down(size, KASAN_GRANULE_SIZE); |
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| 285 | 287 | |
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| 286 | 288 | const void *left_redzone = (const void *)(addr - |
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| 287 | 289 | KASAN_ALLOCA_REDZONE_SIZE); |
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| .. | .. |
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| 289 | 291 | |
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| 290 | 292 | WARN_ON(!IS_ALIGNED(addr, KASAN_ALLOCA_REDZONE_SIZE)); |
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| 291 | 293 | |
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| 292 | | - kasan_unpoison_shadow((const void *)(addr + rounded_down_size), |
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| 293 | | - size - rounded_down_size); |
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| 294 | | - kasan_poison_shadow(left_redzone, KASAN_ALLOCA_REDZONE_SIZE, |
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| 295 | | - KASAN_ALLOCA_LEFT); |
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| 296 | | - kasan_poison_shadow(right_redzone, |
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| 297 | | - padding_size + KASAN_ALLOCA_REDZONE_SIZE, |
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| 298 | | - KASAN_ALLOCA_RIGHT); |
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| 294 | + kasan_unpoison((const void *)(addr + rounded_down_size), |
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| 295 | + size - rounded_down_size, false); |
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| 296 | + kasan_poison(left_redzone, KASAN_ALLOCA_REDZONE_SIZE, |
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| 297 | + KASAN_ALLOCA_LEFT, false); |
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| 298 | + kasan_poison(right_redzone, padding_size + KASAN_ALLOCA_REDZONE_SIZE, |
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| 299 | + KASAN_ALLOCA_RIGHT, false); |
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| 299 | 300 | } |
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| 300 | 301 | EXPORT_SYMBOL(__asan_alloca_poison); |
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| 301 | 302 | |
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| .. | .. |
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| 305 | 306 | if (unlikely(!stack_top || stack_top > stack_bottom)) |
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| 306 | 307 | return; |
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| 307 | 308 | |
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| 308 | | - kasan_unpoison_shadow(stack_top, stack_bottom - stack_top); |
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| 309 | + kasan_unpoison(stack_top, stack_bottom - stack_top, false); |
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| 309 | 310 | } |
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| 310 | 311 | EXPORT_SYMBOL(__asan_allocas_unpoison); |
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| 311 | 312 | |
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| .. | .. |
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| 323 | 324 | DEFINE_ASAN_SET_SHADOW(f3); |
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| 324 | 325 | DEFINE_ASAN_SET_SHADOW(f5); |
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| 325 | 326 | DEFINE_ASAN_SET_SHADOW(f8); |
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| 327 | + |
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| 328 | +void kasan_record_aux_stack(void *addr) |
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| 329 | +{ |
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| 330 | + struct page *page = kasan_addr_to_page(addr); |
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| 331 | + struct kmem_cache *cache; |
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| 332 | + struct kasan_alloc_meta *alloc_meta; |
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| 333 | + void *object; |
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| 334 | + |
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| 335 | + if (is_kfence_address(addr) || !(page && PageSlab(page))) |
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| 336 | + return; |
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| 337 | + |
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| 338 | + cache = page->slab_cache; |
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| 339 | + object = nearest_obj(cache, page, addr); |
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| 340 | + alloc_meta = kasan_get_alloc_meta(cache, object); |
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| 341 | + if (!alloc_meta) |
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| 342 | + return; |
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| 343 | + |
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| 344 | + alloc_meta->aux_stack[1] = alloc_meta->aux_stack[0]; |
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| 345 | + alloc_meta->aux_stack[0] = kasan_save_stack(GFP_NOWAIT); |
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| 346 | +} |
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| 347 | + |
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| 348 | +void kasan_set_free_info(struct kmem_cache *cache, |
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| 349 | + void *object, u8 tag) |
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| 350 | +{ |
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| 351 | + struct kasan_free_meta *free_meta; |
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| 352 | + |
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| 353 | + free_meta = kasan_get_free_meta(cache, object); |
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| 354 | + if (!free_meta) |
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| 355 | + return; |
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| 356 | + |
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| 357 | + kasan_set_track(&free_meta->free_track, GFP_NOWAIT); |
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| 358 | + /* The object was freed and has free track set. */ |
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| 359 | + *(u8 *)kasan_mem_to_shadow(object) = KASAN_KMALLOC_FREETRACK; |
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| 360 | +} |
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| 361 | + |
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| 362 | +struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, |
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| 363 | + void *object, u8 tag) |
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| 364 | +{ |
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| 365 | + if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_KMALLOC_FREETRACK) |
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| 366 | + return NULL; |
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| 367 | + /* Free meta must be present with KASAN_KMALLOC_FREETRACK. */ |
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| 368 | + return &kasan_get_free_meta(cache, object)->free_track; |
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| 369 | +} |
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