From: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> commit 936bb4bbbb832f81055328b84e5afe1fc7246a8d upstream. When bogus memory access happens in mem[set,cpy,move]() it's usually caller's fault. So don't blame mem[set,cpy,move]() in bug report, blame the caller instead. Before: BUG: KASAN: out-of-bounds access in memset+0x23/0x40 at <address> After: BUG: KASAN: out-of-bounds access in <memset_caller> at <address> Link: http://lkml.kernel.org/r/1462538722-1574-2-git-send-email-aryabinin@xxxxxxxxxxxxx Signed-off-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Acked-by: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- mm/kasan/kasan.c | 64 +++++++++++++++++++++++++++++-------------------------- 1 file changed, 34 insertions(+), 30 deletions(-) --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -252,32 +252,36 @@ static __always_inline bool memory_is_po return memory_is_poisoned_n(addr, size); } - -static __always_inline void check_memory_region(unsigned long addr, - size_t size, bool write) +static __always_inline void check_memory_region_inline(unsigned long addr, + size_t size, bool write, + unsigned long ret_ip) { if (unlikely(size == 0)) return; if (unlikely((void *)addr < kasan_shadow_to_mem((void *)KASAN_SHADOW_START))) { - kasan_report(addr, size, write, _RET_IP_); + kasan_report(addr, size, write, ret_ip); return; } if (likely(!memory_is_poisoned(addr, size))) return; - kasan_report(addr, size, write, _RET_IP_); + kasan_report(addr, size, write, ret_ip); } -void __asan_loadN(unsigned long addr, size_t size); -void __asan_storeN(unsigned long addr, size_t size); +static void check_memory_region(unsigned long addr, + size_t size, bool write, + unsigned long ret_ip) +{ + check_memory_region_inline(addr, size, write, ret_ip); +} #undef memset void *memset(void *addr, int c, size_t len) { - __asan_storeN((unsigned long)addr, len); + check_memory_region((unsigned long)addr, len, true, _RET_IP_); return __memset(addr, c, len); } @@ -285,8 +289,8 @@ void *memset(void *addr, int c, size_t l #undef memmove void *memmove(void *dest, const void *src, size_t len) { - __asan_loadN((unsigned long)src, len); - __asan_storeN((unsigned long)dest, len); + check_memory_region((unsigned long)src, len, false, _RET_IP_); + check_memory_region((unsigned long)dest, len, true, _RET_IP_); return __memmove(dest, src, len); } @@ -294,8 +298,8 @@ void *memmove(void *dest, const void *sr #undef memcpy void *memcpy(void *dest, const void *src, size_t len) { - __asan_loadN((unsigned long)src, len); - __asan_storeN((unsigned long)dest, len); + check_memory_region((unsigned long)src, len, false, _RET_IP_); + check_memory_region((unsigned long)dest, len, true, _RET_IP_); return __memcpy(dest, src, len); } @@ -484,22 +488,22 @@ void __asan_unregister_globals(struct ka } EXPORT_SYMBOL(__asan_unregister_globals); -#define DEFINE_ASAN_LOAD_STORE(size) \ - void __asan_load##size(unsigned long addr) \ - { \ - check_memory_region(addr, size, false); \ - } \ - EXPORT_SYMBOL(__asan_load##size); \ - __alias(__asan_load##size) \ - void __asan_load##size##_noabort(unsigned long); \ - EXPORT_SYMBOL(__asan_load##size##_noabort); \ - void __asan_store##size(unsigned long addr) \ - { \ - check_memory_region(addr, size, true); \ - } \ - EXPORT_SYMBOL(__asan_store##size); \ - __alias(__asan_store##size) \ - void __asan_store##size##_noabort(unsigned long); \ +#define DEFINE_ASAN_LOAD_STORE(size) \ + void __asan_load##size(unsigned long addr) \ + { \ + check_memory_region_inline(addr, size, false, _RET_IP_);\ + } \ + EXPORT_SYMBOL(__asan_load##size); \ + __alias(__asan_load##size) \ + void __asan_load##size##_noabort(unsigned long); \ + EXPORT_SYMBOL(__asan_load##size##_noabort); \ + void __asan_store##size(unsigned long addr) \ + { \ + check_memory_region_inline(addr, size, true, _RET_IP_); \ + } \ + EXPORT_SYMBOL(__asan_store##size); \ + __alias(__asan_store##size) \ + void __asan_store##size##_noabort(unsigned long); \ EXPORT_SYMBOL(__asan_store##size##_noabort) DEFINE_ASAN_LOAD_STORE(1); @@ -510,7 +514,7 @@ DEFINE_ASAN_LOAD_STORE(16); void __asan_loadN(unsigned long addr, size_t size) { - check_memory_region(addr, size, false); + check_memory_region(addr, size, false, _RET_IP_); } EXPORT_SYMBOL(__asan_loadN); @@ -520,7 +524,7 @@ EXPORT_SYMBOL(__asan_loadN_noabort); void __asan_storeN(unsigned long addr, size_t size) { - check_memory_region(addr, size, true); + check_memory_region(addr, size, true, _RET_IP_); } EXPORT_SYMBOL(__asan_storeN);