Re: [PATCH] btrfs: parent bytenr must be aligned to sector size

[Qu Wenruo <wqu@suse.com>]

On 2023/4/26 19:53, Анастасия Белова wrote:
> From: Anastasia Belova <abelova@astralinux.ru>
> 
> Change nodesize to sectorsize in alignment check
> in print_extent_item. Change requirement in comment.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Fixes: ea57788eb76d ("btrfs: require only sector size alignment for parent eb bytenr")
> Signed-off-by: Anastasia Belova <abelova@astralinux.ru>

Reviewed-by: Qu Wenruo <wqu@suse.com>

A little surprised that a static checker can even find such hidden problem.

Thanks,
Qu
> ---
>   fs/btrfs/print-tree.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/btrfs/print-tree.c b/fs/btrfs/print-tree.c
> index b93c96213304..cee005fb8209 100644
> --- a/fs/btrfs/print-tree.c
> +++ b/fs/btrfs/print-tree.c
> @@ -152,9 +152,9 @@ static void print_extent_item(struct extent_buffer *eb, int slot, int type)
>   			       offset, btrfs_shared_data_ref_count(eb, sref));
>   			/*
>   			 * offset is supposed to be a tree block which
> -			 * must be aligned to nodesize.
> +			 * must be aligned to sectorsize.
>   			 */
> -			if (!IS_ALIGNED(offset, eb->fs_info->nodesize))
> +			if (!IS_ALIGNED(offset, eb->fs_info->sectorsize))
>   				pr_info(
>   			"\t\t\t(parent %llu not aligned to sectorsize %u)\n",
>   				     offset, eb->fs_info->sectorsize);