From: Kees Cook Date: Fri, 15 Sep 2023 20:04:08 +0000 (-0700) Subject: dm: Annotate struct dm_bio_prison with __counted_by X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=96d7c65939793c2efc16e43c81a92aed9eed0d78;p=linux.git dm: Annotate struct dm_bio_prison with __counted_by Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct dm_bio_prison. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Alasdair Kergon Cc: Mike Snitzer Cc: dm-devel@redhat.com Reviewed-by: "Gustavo A. R. Silva" Link: https://lore.kernel.org/r/20230915200407.never.611-kees@kernel.org Signed-off-by: Kees Cook --- diff --git a/drivers/md/dm-bio-prison-v1.c b/drivers/md/dm-bio-prison-v1.c index 92afdca760aeb..9ab32abe5ed4d 100644 --- a/drivers/md/dm-bio-prison-v1.c +++ b/drivers/md/dm-bio-prison-v1.c @@ -26,7 +26,7 @@ struct prison_region { struct dm_bio_prison { mempool_t cell_pool; unsigned int num_locks; - struct prison_region regions[]; + struct prison_region regions[] __counted_by(num_locks); }; static struct kmem_cache *_cell_cache;