nfsd: Fix error cleanup path in nfsd_rename()

[ Upstream commit 9fe6e9e7b58944037714442384075c17cfde1c56 ]

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>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index b7c7a9273ea01d9d84bcc2ea487bd6d886bc060d..4ed1e83defa23d08d0dfe54579b5a823cf5bade7 100644 (file)
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1833,7 +1833,7 @@ 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)
@@ -1903,6 +1903,7 @@ 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);
 
        /*