Re: [PATCH] btrfs: Annotate structs with __counted_by()
From: Johannes Thumshirn
Date: Mon Aug 12 2024 - 06:55:11 EST
On 12.08.24 12:37, Thorsten Blum wrote:
> 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) + \
Looks good to me,
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Out of curiosity, have you encountered any issues with this patch applied?