With skbuff's post-allocation use of ksize() rearranged to use kmalloc_size_round() prior to allocation, the compiler can correctly reason about the size of these allocations. The prior mismatch had caused buffer overflow mitigations to erroneously fire under CONFIG_UBSAN_BOUNDS, requiring a partial revert of the __alloc_size attributes. Restore the attribute that had been removed in commit 93dd04ab0b2b ("slab: remove __alloc_size attribute from __kmalloc_track_caller").
Cc: Christoph Lameter <c...@linux.com> Cc: Pekka Enberg <penb...@kernel.org> Cc: David Rientjes <rient...@google.com> Cc: Joonsoo Kim <iamjoonsoo....@lge.com> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Vlastimil Babka <vba...@suse.cz> Cc: Roman Gushchin <roman.gushc...@linux.dev> Cc: Hyeonggon Yoo <42.hye...@gmail.com> Cc: linux...@kvack.org Signed-off-by: Kees Cook <keesc...@chromium.org> --- include/linux/slab.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/slab.h b/include/linux/slab.h index 727640173568..297b85ed2c29 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -693,7 +693,8 @@ static inline __alloc_size(1, 2) void *kcalloc(size_t n, size_t size, gfp_t flag * allocator where we care about the real place the memory allocation * request comes from. */ -extern void *__kmalloc_track_caller(size_t size, gfp_t flags, unsigned long caller); +extern void *__kmalloc_track_caller(size_t size, gfp_t flags, unsigned long caller) + __alloc_size(1); #define kmalloc_track_caller(size, flags) \ __kmalloc_track_caller(size, flags, _RET_IP_) -- 2.34.1