kasan: fix tag for large allocations when using CONFIG_SLAB
authorMatthew Wilcox (Oracle) <willy@infradead.org>
Fri, 5 Nov 2021 20:35:53 +0000 (13:35 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sat, 6 Nov 2021 20:30:33 +0000 (13:30 -0700)
commit820a1e6e87ccaa6c0c77ac7d79d05beec3f8cb88
tree63574d9076436d646ac4f95ccd1ce5d7c4280716
parentf70da745be4d4c367568b8345f50db1ae04efcb2
kasan: fix tag for large allocations when using CONFIG_SLAB

If an object is allocated on a tail page of a multi-page slab, kasan
will get the wrong tag because page->s_mem is NULL for tail pages.  I'm
not quite sure what the user-visible effect of this might be.

Link: https://lkml.kernel.org/r/20211001024105.3217339-1-willy@infradead.org
Fixes: 7f94ffbc4c6a ("kasan: add hooks implementation for tag-based mode")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.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>
mm/kasan/common.c