From 047d711a7a3e6e9b84f19c594a8bb3af04384e69 Mon Sep 17 00:00:00 2001 From: Andrey Ryabinin Date: Fri, 20 May 2016 16:59:28 -0700 Subject: [PATCH] mm/kasan: add API to check memory regions commit 64f8ebaf115bcddc4aaa902f981c57ba6506bc42 upstream. Memory access coded in an assembly won't be seen by KASAN as a compiler can instrument only C code. Add kasan_check_[read,write]() API which is going to be used to check a certain memory range. Link: http://lkml.kernel.org/r/1462538722-1574-3-git-send-email-aryabinin@virtuozzo.com Signed-off-by: Andrey Ryabinin Acked-by: Alexander Potapenko Cc: Dmitry Vyukov Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [bwh: Backported to 4.4: drop change in MAINTAINERS] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- include/linux/kasan-checks.h | 12 ++++++++++++ mm/kasan/kasan.c | 12 ++++++++++++ 2 files changed, 24 insertions(+) create mode 100644 include/linux/kasan-checks.h diff --git a/include/linux/kasan-checks.h b/include/linux/kasan-checks.h new file mode 100644 index 0000000000000..b7f8aced78707 --- /dev/null +++ b/include/linux/kasan-checks.h @@ -0,0 +1,12 @@ +#ifndef _LINUX_KASAN_CHECKS_H +#define _LINUX_KASAN_CHECKS_H + +#ifdef CONFIG_KASAN +void kasan_check_read(const void *p, unsigned int size); +void kasan_check_write(const void *p, unsigned int size); +#else +static inline void kasan_check_read(const void *p, unsigned int size) { } +static inline void kasan_check_write(const void *p, unsigned int size) { } +#endif + +#endif diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index b80d86d905c2a..410b0fcb0c733 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -278,6 +278,18 @@ static void check_memory_region(unsigned long addr, check_memory_region_inline(addr, size, write, ret_ip); } +void kasan_check_read(const void *p, unsigned int size) +{ + check_memory_region((unsigned long)p, size, false, _RET_IP_); +} +EXPORT_SYMBOL(kasan_check_read); + +void kasan_check_write(const void *p, unsigned int size) +{ + check_memory_region((unsigned long)p, size, true, _RET_IP_); +} +EXPORT_SYMBOL(kasan_check_write); + #undef memset void *memset(void *addr, int c, size_t len) { -- 2.47.2