Re: [PATCH v5] xfs: introduce protection for drop nlink

[Darrick J. Wong]

On Mon, Oct 09, 2023 at 04:45:57PM +0800, cheng.lin130@xxxxxxxxxx wrote:
> From: Cheng Lin <cheng.lin130@xxxxxxxxxx>
> When abnormal drop_nlink are detected on the inode,
> return error, to avoid corruption propagation.
> 
> Signed-off-by: Cheng Lin <cheng.lin130@xxxxxxxxxx>
> ---
>  fs/xfs/xfs_inode.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
> index 9e62cc500..752e6aeba 100644
> --- a/fs/xfs/xfs_inode.c
> +++ b/fs/xfs/xfs_inode.c
> @@ -919,6 +919,14 @@ xfs_droplink(
>  	xfs_trans_t *tp,
>  	xfs_inode_t *ip)
>  {
> +

No need for the extra whitespace here.

> +	if (VFS_I(ip)->i_nlink == 0) {
> +		xfs_alert(ip->i_mount,
> +			  "%s: Attempt to drop inode (%llu) with nlink zero.",
> +			  __func__, ip->i_ino);
> +		return -EFSCORRUPTED;
> +	}

With that fixed,
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>

--D

> +
>  	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
> 
>  	drop_nlink(VFS_I(ip));
> -- 
> 2.18.1