kasan: improve double-free reports
Currently we just dump stack in case of double free bug.
Let's dump all info about the object that we have.
[aryabinin@virtuozzo.com: change double free message per Alexander]
Link: http://lkml.kernel.org/r/1470153654-30160-1-git-send-email-aryabinin@virtuozzo.com
Link: http://lkml.kernel.org/r/1470062715-14077-6-git-send-email-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c
index 92750e3..88af13c 100644
--- a/mm/kasan/kasan.c
+++ b/mm/kasan/kasan.c
@@ -543,8 +543,7 @@
shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(object));
if (shadow_byte < 0 || shadow_byte >= KASAN_SHADOW_SCALE_SIZE) {
- pr_err("Double free");
- dump_stack();
+ kasan_report_double_free(cache, object, shadow_byte);
return true;
}