[PATCH] btrfs: Annotate structs with __counted_by()

From: Thorsten Blum
Date: Mon Aug 12 2024 - 06:37:10 EST


Add the __counted_by compiler attribute to the flexible array member
stripes to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
CONFIG_FORTIFY_SOURCE.

Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxxx>
---
fs/btrfs/volumes.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 37a09ebb34dd..f28fa318036b 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -551,7 +551,7 @@ struct btrfs_io_context {
* stripes[data_stripes + 1]: The Q stripe (only for RAID6).
*/
u64 full_stripe_logical;
- struct btrfs_io_stripe stripes[];
+ struct btrfs_io_stripe stripes[] __counted_by(num_stripes);
};

struct btrfs_device_info {
@@ -591,7 +591,7 @@ struct btrfs_chunk_map {
int io_width;
int num_stripes;
int sub_stripes;
- struct btrfs_io_stripe stripes[];
+ struct btrfs_io_stripe stripes[] __counted_by(num_stripes);
};

#define btrfs_chunk_map_size(n) (sizeof(struct btrfs_chunk_map) + \
--
2.46.0