kasan: Fix a type conversion error

The current KASAN code can not find the following out-of-bounds bugs:

        char *ptr;
        ptr = kmalloc(8, GFP_KERNEL);
        memset(ptr+7, 0, 2);

the cause of the problem is the type conversion error in
*memory_is_poisoned_n* function.  So this patch fix that.

Signed-off-by: Wang Long <long.wanglong@huawei.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Wang Long 2015-11-05 18:51:18 -08:00 committed by Linus Torvalds
parent f523e737c0
commit e0d5771439

View file

@ -203,7 +203,7 @@ static __always_inline bool memory_is_poisoned_n(unsigned long addr,
s8 *last_shadow = (s8 *)kasan_mem_to_shadow((void *)last_byte);
if (unlikely(ret != (unsigned long)last_shadow ||
((last_byte & KASAN_SHADOW_MASK) >= *last_shadow)))
((long)(last_byte & KASAN_SHADOW_MASK) >= *last_shadow)))
return true;
}
return false;