diff mbox series

[5.10,163/243] SUNRPC: prevent port reuse on transports which dont request it.

Message ID 20210719144946.160122928@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman July 19, 2021, 2:53 p.m. UTC
From: NeilBrown <neilb@suse.de>

[ Upstream commit bc1c56e9bbe92766d017efb5f0a0c71f80da5570 ]

If an RPC client is created without RPC_CLNT_CREATE_REUSEPORT, it should
not reuse the source port when a TCP connection is re-established.
This is currently implemented by preventing the source port being
recorded after a successful connection (the call to xs_set_srcport()).

However the source port is also recorded after a successful bind in xs_bind().
This may not be needed at all and certainly is not wanted when
RPC_CLNT_CREATE_REUSEPORT wasn't requested.

So avoid that assignment when xprt.reuseport is not set.

With this change, NFSv4.1 and later mounts use a different port number on
each connection.  This is helpful with some firewalls which don't cope
well with port reuse.

Signed-off-by: NeilBrown <neilb@suse.de>
Fixes: e6237b6feb37 ("NFSv4.1: Don't rebind to the same source port when reconnecting to the server")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/sunrpc/xprtsock.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index c56a66cdf4ac..9c0f71e82d97 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1680,7 +1680,8 @@  static int xs_bind(struct sock_xprt *transport, struct socket *sock)
 		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
 				transport->xprt.addrlen);
 		if (err == 0) {
-			transport->srcport = port;
+			if (transport->xprt.reuseport)
+				transport->srcport = port;
 			break;
 		}
 		last = port;