From: Benjamin Coddington <bcodding@redhat.com>
Date: Fri, 22 Sep 2017 07:57:10 -0400
Subject: [PATCH] NFS: Fix uninitialized rpc_wait_queue
Git-commit: 68ebf8fe3bce8c167cf83fbd681c1eb1ed419c6c
Patch-mainline: v4.14-rc5
References: git-fixes

Michael Sterrett reports a NULL pointer dereference on NFSv3 mounts when
CONFIG_NFS_V4 is not set because the NFS UOC rpc_wait_queue has not been
initialized.  Move the initialization of the queue out of the CONFIG_NFS_V4
conditional setion.

Fixes: 7d6ddf88c4db ("NFS: Add an iocounter wait function for async RPC tasks")
Cc: stable@vger.kernel.org # 4.11+
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Acked-by: NeilBrown <neilb@suse.com>

---
 fs/nfs/client.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -219,7 +219,6 @@ static void nfs_cb_idr_remove_locked(str
 static void pnfs_init_server(struct nfs_server *server)
 {
 	rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
-	rpc_init_wait_queue(&server->uoc_rpcwaitq, "NFS UOC");
 }
 
 #else
@@ -892,6 +891,7 @@ struct nfs_server *nfs_alloc_server(void
 	ida_init(&server->openowner_id);
 	ida_init(&server->lockowner_id);
 	pnfs_init_server(server);
+	rpc_init_wait_queue(&server->uoc_rpcwaitq, "NFS UOC");
 
 	return server;
 }