From 64f8ebaf115bcddc4aaa902f981c57ba6506bc42 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 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 --- MAINTAINERS | 2 +- include/linux/kasan-checks.h | 12 ++++++++++++ mm/kasan/kasan.c | 12 ++++++++++++ 3 files changed, 25 insertions(+), 1 deletion(-) create mode 100644 include/linux/kasan-checks.h diff --git a/MAINTAINERS b/MAINTAINERS index 374ffa2d81b7..8b92445561b6 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6242,7 +6242,7 @@ S: Maintained F: arch/*/include/asm/kasan.h F: arch/*/mm/kasan_init* F: Documentation/kasan.txt -F: include/linux/kasan.h +F: include/linux/kasan*.h F: lib/test_kasan.c F: mm/kasan/ F: scripts/Makefile.kasan diff --git a/include/linux/kasan-checks.h b/include/linux/kasan-checks.h new file mode 100644 index 000000000000..b7f8aced7870 --- /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 e5beb40d97b1..18b6a2b8d183 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -299,6 +299,18 @@ 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) { -- 2.25.1