diff options
author | Andrey Ryabinin <a.ryabinin@samsung.com> | 2015-02-13 23:39:28 +0100 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-14 06:21:41 +0100 |
commit | b8c73fc2493d42517be95cf2c89659fc6c6f4d02 (patch) | |
tree | 81e44f58a903a8093617f5db7806f0bfa4cf5691 /mm/kasan | |
parent | x86_64: add KASan support (diff) | |
download | linux-b8c73fc2493d42517be95cf2c89659fc6c6f4d02.tar.xz linux-b8c73fc2493d42517be95cf2c89659fc6c6f4d02.zip |
mm: page_alloc: add kasan hooks on alloc and free paths
Add kernel address sanitizer hooks to mark allocated page's addresses as
accessible in corresponding shadow region. Mark freed pages as
inaccessible.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/kasan')
-rw-r--r-- | mm/kasan/kasan.c | 14 | ||||
-rw-r--r-- | mm/kasan/kasan.h | 2 | ||||
-rw-r--r-- | mm/kasan/report.c | 11 |
3 files changed, 27 insertions, 0 deletions
diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index def81104772f..b516eb8632b9 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -254,6 +254,20 @@ static __always_inline void check_memory_region(unsigned long addr, kasan_report(addr, size, write, _RET_IP_); } +void kasan_alloc_pages(struct page *page, unsigned int order) +{ + if (likely(!PageHighMem(page))) + kasan_unpoison_shadow(page_address(page), PAGE_SIZE << order); +} + +void kasan_free_pages(struct page *page, unsigned int order) +{ + if (likely(!PageHighMem(page))) + kasan_poison_shadow(page_address(page), + PAGE_SIZE << order, + KASAN_FREE_PAGE); +} + #define DEFINE_ASAN_LOAD_STORE(size) \ void __asan_load##size(unsigned long addr) \ { \ diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index 648b9c006f3f..d3c90d5dd97a 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -6,6 +6,8 @@ #define KASAN_SHADOW_SCALE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT) #define KASAN_SHADOW_MASK (KASAN_SHADOW_SCALE_SIZE - 1) +#define KASAN_FREE_PAGE 0xFF /* page was freed */ + struct kasan_access_info { const void *access_addr; const void *first_bad_addr; diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 5835d69563f5..fab8e7882ff1 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -54,6 +54,9 @@ static void print_error_description(struct kasan_access_info *info) shadow_val = *(u8 *)kasan_mem_to_shadow(info->first_bad_addr); switch (shadow_val) { + case KASAN_FREE_PAGE: + bug_type = "use after free"; + break; case 0 ... KASAN_SHADOW_SCALE_SIZE - 1: bug_type = "out of bounds access"; break; @@ -69,6 +72,14 @@ static void print_error_description(struct kasan_access_info *info) static void print_address_description(struct kasan_access_info *info) { + const void *addr = info->access_addr; + + if ((addr >= (void *)PAGE_OFFSET) && + (addr < high_memory)) { + struct page *page = virt_to_head_page(addr); + dump_page(page, "kasan: bad access detected"); + } + dump_stack(); } |