[PATCH 4.4 059/104] sunrpc: handle ENOMEM in rpcb_getport_async

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: J. Bruce Fields <bfields@xxxxxxxxxx>

commit 81c88b18de1f11f70c97f28ced8d642c00bb3955 upstream.

If we ignore the error we'll hit a null dereference a little later.

Reported-by: syzbot+4b98281f2401ab849f4b@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx>
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 net/sunrpc/rpcb_clnt.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -772,6 +772,12 @@ void rpcb_getport_async(struct rpc_task
 	case RPCBVERS_3:
 		map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID];
 		map->r_addr = rpc_sockaddr2uaddr(sap, GFP_ATOMIC);
+		if (!map->r_addr) {
+			status = -ENOMEM;
+			dprintk("RPC: %5u %s: no memory available\n",
+				task->tk_pid, __func__);
+			goto bailout_free_args;
+		}
 		map->r_owner = "";
 		break;
 	case RPCBVERS_2:
@@ -794,6 +800,8 @@ void rpcb_getport_async(struct rpc_task
 	rpc_put_task(child);
 	return;
 
+bailout_free_args:
+	kfree(map);
 bailout_release_client:
 	rpc_release_client(rpcb_clnt);
 bailout_nofree: