NFS: get module in idmap PipeFS notifier callback

This is bug fix. Notifier callback is called from SUNRPC module. So before dereferencing NFS module we have to make sure, that it's alive. Signed-off-by: Stanislav Kinsbursky <[email protected]> Signed-off-by: Trond Myklebust <[email protected]>
cbmeeks · Apr 28, 2012 · 71dfc5f · 71dfc5f
1 parent e245d42
commit 71dfc5f
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
@@ -554,12 +554,16 @@ static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
 	struct nfs_client *clp;
 	int error = 0;
 
+	if (!try_module_get(THIS_MODULE))
+		return 0;
+
 	while ((clp = nfs_get_client_for_event(sb->s_fs_info, event))) {
 		error = __rpc_pipefs_event(clp, event, sb);
 		nfs_put_client(clp);
 		if (error)
 			break;
 	}
+	module_put(THIS_MODULE);
 	return error;
 }