1 files changed, 38 insertions, 21 deletions

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index abb40c140738..b5544514ee57 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1276,34 +1276,53 @@ static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
         }
 }
 
+static unsigned short xs_get_srcport(struct sock_xprt *transport, struct socket *sock)
+{
+        unsigned short port = transport->port;
+
+        if (port == 0 && transport->xprt.resvport)
+                port = xs_get_random_port();
+        return port;
+}
+
+static unsigned short xs_next_srcport(struct sock_xprt *transport, struct socket *sock, unsigned short port)
+{
+        if (transport->port != 0)
+                transport->port = 0;
+        if (!transport->xprt.resvport)
+                return 0;
+        if (port <= xprt_min_resvport || port > xprt_max_resvport)
+                return xprt_max_resvport;
+        return --port;
+}
+
 static int xs_bind4(struct sock_xprt *transport, struct socket *sock)
 {
         struct sockaddr_in myaddr = {
                 .sin_family = AF_INET,
         };
         struct sockaddr_in *sa;
-        int err;
-        unsigned short port = transport->port;
+        int err, nloop = 0;
+        unsigned short port = xs_get_srcport(transport, sock);
+        unsigned short last;
 
-        if (!transport->xprt.resvport)
-                port = 0;
         sa = (struct sockaddr_in *)&transport->addr;
         myaddr.sin_addr = sa->sin_addr;
         do {
                 myaddr.sin_port = htons(port);
                 err = kernel_bind(sock, (struct sockaddr *) &myaddr,
                                                 sizeof(myaddr));
-                if (!transport->xprt.resvport)
+                if (port == 0)
                         break;
                 if (err == 0) {
                         transport->port = port;
                         break;
                 }
-                if (port <= xprt_min_resvport)
-                        port = xprt_max_resvport;
-                else
-                        port--;
-        } while (err == -EADDRINUSE && port != transport->port);
+                last = port;
+                port = xs_next_srcport(transport, sock, port);
+                if (port > last)
+                        nloop++;
+        } while (err == -EADDRINUSE && nloop != 2);
         dprintk("RPC:       %s "NIPQUAD_FMT":%u: %s (%d)\n",
                         __FUNCTION__, NIPQUAD(myaddr.sin_addr),
                         port, err ? "failed" : "ok", err);
@@ -1316,28 +1335,27 @@ static int xs_bind6(struct sock_xprt *transport, struct socket *sock)
                 .sin6_family = AF_INET6,
         };
         struct sockaddr_in6 *sa;
-        int err;
-        unsigned short port = transport->port;
+        int err, nloop = 0;
+        unsigned short port = xs_get_srcport(transport, sock);
+        unsigned short last;
 
-        if (!transport->xprt.resvport)
-                port = 0;
         sa = (struct sockaddr_in6 *)&transport->addr;
         myaddr.sin6_addr = sa->sin6_addr;
         do {
                 myaddr.sin6_port = htons(port);
                 err = kernel_bind(sock, (struct sockaddr *) &myaddr,
                                                 sizeof(myaddr));
-                if (!transport->xprt.resvport)
+                if (port == 0)
                         break;
                 if (err == 0) {
                         transport->port = port;
                         break;
                 }
-                if (port <= xprt_min_resvport)
-                        port = xprt_max_resvport;
-                else
-                        port--;
-        } while (err == -EADDRINUSE && port != transport->port);
+                last = port;
+                port = xs_next_srcport(transport, sock, port);
+                if (port > last)
+                        nloop++;
+        } while (err == -EADDRINUSE && nloop != 2);
         dprintk("RPC:       xs_bind6 "NIP6_FMT":%u: %s (%d)\n",
                 NIP6(myaddr.sin6_addr), port, err ? "failed" : "ok", err);
         return err;
@@ -1819,7 +1837,6 @@ static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
         xprt->addrlen = args->addrlen;
         if (args->srcaddr)
                 memcpy(&new->addr, args->srcaddr, args->addrlen);
-        new->port = xs_get_random_port();
 
         return xprt;
 }