NFS: Prevent resource leak in nfs_alloc_server()

commit d189f22 upstream.

It was overlooked to call ida_free() after a failed nfs_alloc_iostats() call.
Thus add the missed function call in an if branch.

Fixes: 1c72511 ("NFS: add superblock sysfs entries")
Cc: stable@vger.kernel.org
Reported-by: Christophe Jaillet <christophe.jaillet@wanadoo.fr>
Closes: https://lore.kernel.org/linux-nfs/1c8e10c9-def7-4f0d-8aa1-23c8035a38c8@wanadoo.fr/
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: elfring

fs/nfs/client.c

@@ -1070,6 +1070,7 @@ struct nfs_server *nfs_alloc_server(void)
 
 	server->io_stats = nfs_alloc_iostats();
 	if (!server->io_stats) {
+		ida_free(&s_sysfs_ids, server->s_sysfs_id);
 		kfree(server);
 		return NULL;
 	}