netfs: Prevent duplicate unlocking

The filio lock has been released here, so there is no need to jump to
error_folio_unlock to release it again.

Reported-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=b73c7d94a151e2ee1e9b
Signed-off-by: Lizhi Xu <[email protected]>
Acked-by: David Howells <[email protected]>
Reviewed-by: Paulo Alcantara (Red Hat) <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

Author: Lizhi Xu

fs/netfs/buffered_write.c

@@ -347,7 +347,7 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter,
 		folio_put(folio);
 		ret = filemap_write_and_wait_range(mapping, fpos, fpos + flen - 1);
 		if (ret < 0)
-			goto error_folio_unlock;
+			goto out;
 		continue;
 
 	copied: