BACKPORT: 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 <aryabinin@virtuozzo.com>
Acked-by: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Bug: 64145065
(cherry-picked from 64f8ebaf115bcddc4aaa902f981c57ba6506bc42)
Change-Id: I3e75c7c22e77d390c55ca1b86ec58a6d6ea1da87
Signed-off-by: Paul Lawrence <paullawrence@google.com>
This commit is contained in:
Andrey Ryabinin 2016-05-20 16:59:28 -07:00 committed by Paul Lawrence
parent d8688d3bac
commit ec4cb91ee5
3 changed files with 38 additions and 0 deletions

View file

@ -5982,6 +5982,20 @@ S: Maintained
F: Documentation/hwmon/k8temp
F: drivers/hwmon/k8temp.c
KASAN
M: Andrey Ryabinin <aryabinin@virtuozzo.com>
R: Alexander Potapenko <glider@google.com>
R: Dmitry Vyukov <dvyukov@google.com>
L: kasan-dev@googlegroups.com
S: Maintained
F: arch/*/include/asm/kasan.h
F: arch/*/mm/kasan_init*
F: Documentation/kasan.txt
F: include/linux/kasan*.h
F: lib/test_kasan.c
F: mm/kasan/
F: scripts/Makefile.kasan
KCONFIG
M: "Yann E. MORIN" <yann.morin.1998@free.fr>
L: linux-kbuild@vger.kernel.org

View file

@ -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

View file

@ -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)
{