From 96d7c65939793c2efc16e43c81a92aed9eed0d78 Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@chromium.org>
Date: Fri, 15 Sep 2023 13:04:08 -0700
Subject: [PATCH] dm: Annotate struct dm_bio_prison with __counted_by
Git-commit: 96d7c65939793c2efc16e43c81a92aed9eed0d78
Patch-mainline: v6.7-rc1
References: jsc#PED-7514
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 <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: dm-devel@redhat.com
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915200407.never.611-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Coly Li <colyli@suse.de>
---
drivers/md/dm-bio-prison-v1.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/md/dm-bio-prison-v1.c b/drivers/md/dm-bio-prison-v1.c
index 92afdca760ae..9ab32abe5ed4 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;
--
2.35.3