From: Kees Cook Date: Fri, 15 Sep 2023 20:03:45 +0000 (-0700) Subject: dm crypt: Annotate struct crypt_config with __counted_by X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=6521ba56ca86c19328f956090e367eacee4eb9d1;p=linux.git dm crypt: Annotate struct crypt_config 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 crypt_config. [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/20230915200344.never.272-kees@kernel.org Signed-off-by: Kees Cook --- diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index f2662c21a6dfe..f276e9460feb4 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -224,7 +224,7 @@ struct crypt_config { struct mutex bio_alloc_lock; u8 *authenc_key; /* space for keys in authenc() format (if used) */ - u8 key[]; + u8 key[] __counted_by(key_size); }; #define MIN_IOS 64