kasan, slub: reset tag when printing address
authorKuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Fri, 13 Aug 2021 23:54:27 +0000 (16:54 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 18 Aug 2021 07:07:08 +0000 (09:07 +0200)
commit 340caf178ddc2efb0294afaf54c715f7928c258e upstream.

The address still includes the tags when it is printed.  With hardware
tag-based kasan enabled, we will get a false positive KASAN issue when
we access metadata.

Reset the tag before we access the metadata.

Link: https://lkml.kernel.org/r/20210804090957.12393-3-Kuan-Ying.Lee@mediatek.com
Fixes: aa1ef4d7b3f6 ("kasan, mm: reset tags when accessing metadata")
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Nicholas Tang <nicholas.tang@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mm/slub.c

index 61bd40e3eb9a4f3b213b2364439a5df46bf23150..e32ded30506e848340d1158127fbf427a9cfcdb9 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -551,8 +551,8 @@ static void print_section(char *level, char *text, u8 *addr,
                          unsigned int length)
 {
        metadata_access_enable();
-       print_hex_dump(level, kasan_reset_tag(text), DUMP_PREFIX_ADDRESS,
-                       16, 1, addr, length, 1);
+       print_hex_dump(level, text, DUMP_PREFIX_ADDRESS,
+                       16, 1, kasan_reset_tag((void *)addr), length, 1);
        metadata_access_disable();
 }