SUNRPC: Fix an rpcbind breakage for the case of IPv6 lookups

Now that rpcb_next_version has been split into an IPv4 version and an IPv6
version, we Oops when rpcb_call_async attempts to look up the IPv6-specific
RPC procedure in rpcb_next_version.

Fix the Oops simply by having rpcb_getport_async pass the correct RPC
procedure as an argument.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/rpcb_clnt.c

@@ -243,10 +243,10 @@ int rpcb_getport_sync(struct sockaddr_in *sin, u32 prog, u32 vers, int prot)
 }
 EXPORT_SYMBOL_GPL(rpcb_getport_sync);
 
-static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, int version)
+static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, struct rpc_procinfo *proc)
 {
 	struct rpc_message msg = {
-		.rpc_proc = rpcb_next_version[version].rpc_proc,
+		.rpc_proc = proc,
 		.rpc_argp = map,
 		.rpc_resp = &map->r_port,
 	};
@@ -271,6 +271,7 @@ static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbi
 void rpcb_getport_async(struct rpc_task *task)
 {
 	struct rpc_clnt *clnt = task->tk_client;
+	struct rpc_procinfo *proc;
 	u32 bind_version;
 	struct rpc_xprt *xprt = task->tk_xprt;
 	struct rpc_clnt	*rpcb_clnt;
@@ -280,7 +281,6 @@ void rpcb_getport_async(struct rpc_task *task)
 	struct sockaddr *sap = (struct sockaddr *)&addr;
 	size_t salen;
 	int status;
-	struct rpcb_info *info;
 
 	dprintk("RPC: %5u %s(%s, %u, %u, %d)\n",
 		task->tk_pid, __func__,
@@ -313,10 +313,12 @@ void rpcb_getport_async(struct rpc_task *task)
 	/* Don't ever use rpcbind v2 for AF_INET6 requests */
 	switch (sap->sa_family) {
 	case AF_INET:
-		info = rpcb_next_version;
+		proc = rpcb_next_version[xprt->bind_index].rpc_proc;
+		bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
 		break;
 	case AF_INET6:
-		info = rpcb_next_version6;
+		proc = rpcb_next_version6[xprt->bind_index].rpc_proc;
+		bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers;
 		break;
 	default:
 		status = -EAFNOSUPPORT;
@@ -324,14 +326,13 @@ void rpcb_getport_async(struct rpc_task *task)
 				task->tk_pid, __func__);
 		goto bailout_nofree;
 	}
-	if (info[xprt->bind_index].rpc_proc == NULL) {
+	if (proc == NULL) {
 		xprt->bind_index = 0;
 		status = -EPFNOSUPPORT;
 		dprintk("RPC: %5u %s: no more getport versions available\n",
 			task->tk_pid, __func__);
 		goto bailout_nofree;
 	}
-	bind_version = info[xprt->bind_index].rpc_vers;
 
 	dprintk("RPC: %5u %s: trying rpcbind version %u\n",
 		task->tk_pid, __func__, bind_version);
@@ -361,7 +362,7 @@ void rpcb_getport_async(struct rpc_task *task)
 	map->r_addr = rpc_peeraddr2str(rpcb_clnt, RPC_DISPLAY_UNIVERSAL_ADDR);
 	map->r_owner = RPCB_OWNER_STRING;	/* ignored for GETADDR */
 
-	child = rpcb_call_async(rpcb_clnt, map, xprt->bind_index);
+	child = rpcb_call_async(rpcb_clnt, map, proc);
 	rpc_release_client(rpcb_clnt);
 	if (IS_ERR(child)) {
 		status = -EIO;