Re: [PATCH] nfsd: Fix error cleanup path in nfsd_rename()

[Chuck Lever <chuck.lever@oracle.com>]

On Mon, Mar 18, 2024 at 05:32:09PM +0100, Jan Kara wrote:
> Commit a8b0026847b8 ("rename(): avoid a deadlock in the case of parents
> having no common ancestor") added an error bail out path. However this
> path does not drop the remount protection that has been acquired. Fix
> the cleanup path to properly drop the remount protection.
> 
> Fixes: a8b0026847b8 ("rename(): avoid a deadlock in the case of parents having no common ancestor")
> Signed-off-by: Jan Kara <jack@suse.cz>

Al, Jan, let me know if you'd like me to take this through the
nfsd tree for v6.9-rc. If not:

Acked-by: Chuck Lever <chuck.lever@oracle.com>


> ---
>  fs/nfsd/vfs.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index 6a9464262fae..2e41eb4c3cec 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -1852,7 +1852,7 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
>  	trap = lock_rename(tdentry, fdentry);
>  	if (IS_ERR(trap)) {
>  		err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev;
> -		goto out;
> +		goto out_want_write;
>  	}
>  	err = fh_fill_pre_attrs(ffhp);
>  	if (err != nfs_ok)
> @@ -1922,6 +1922,7 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
>  	}
>  out_unlock:
>  	unlock_rename(tdentry, fdentry);
> +out_want_write:
>  	fh_drop_write(ffhp);
>  
>  	/*
> -- 
> 2.35.3
> 

-- 
Chuck Lever