[ 3.5.yuz extended stable ] Patch "SUNRPC: Ensure that the TCP socket is closed when in" has been added to staging queue

[Herton Ronaldo Krzesinski]

This is a note to let you know that I have just added a patch titled

    SUNRPC: Ensure that the TCP socket is closed when in

to the linux-3.5.y-queue branch of the 3.5.yuz extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.yuz tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Herton

------

>From 468d26bc447f673a9433718188eb5105bd631eaa Mon Sep 17 00:00:00 2001
From: Trond Myklebust <Trond.Myklebust at netapp.com>
Date: Wed, 12 Sep 2012 16:49:15 -0400
Subject: [PATCH] SUNRPC: Ensure that the TCP socket is closed when in
 CLOSE_WAIT

commit a519fc7a70d1a918574bb826cc6905b87b482eb9 upstream.

Instead of doing a shutdown() call, we need to do an actual close().
Ditto if/when the server is sending us junk RPC headers.

Signed-off-by: Trond Myklebust <Trond.Myklebust at netapp.com>
Tested-by: Simon Kirby <sim at hostway.ca>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 net/sunrpc/xprtsock.c |   21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index b88c6bf..00ff343 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1028,6 +1028,16 @@ static void xs_udp_data_ready(struct sock *sk, int len)
 	read_unlock_bh(&sk->sk_callback_lock);
 }

+/*
+ * Helper function to force a TCP close if the server is sending
+ * junk and/or it has put us in CLOSE_WAIT
+ */
+static void xs_tcp_force_close(struct rpc_xprt *xprt)
+{
+	set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
+	xprt_force_disconnect(xprt);
+}
+
 static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
 {
 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
@@ -1054,7 +1064,7 @@ static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_rea
 	/* Sanity check of the record length */
 	if (unlikely(transport->tcp_reclen < 8)) {
 		dprintk("RPC:       invalid TCP record fragment length\n");
-		xprt_force_disconnect(xprt);
+		xs_tcp_force_close(xprt);
 		return;
 	}
 	dprintk("RPC:       reading TCP record fragment of length %d\n",
@@ -1135,7 +1145,7 @@ static inline void xs_tcp_read_calldir(struct sock_xprt *transport,
 		break;
 	default:
 		dprintk("RPC:       invalid request message type\n");
-		xprt_force_disconnect(&transport->xprt);
+		xs_tcp_force_close(&transport->xprt);
 	}
 	xs_tcp_check_fraghdr(transport);
 }
@@ -1458,6 +1468,8 @@ static void xs_tcp_cancel_linger_timeout(struct rpc_xprt *xprt)
 static void xs_sock_mark_closed(struct rpc_xprt *xprt)
 {
 	smp_mb__before_clear_bit();
+	clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
+	clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
 	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 	clear_bit(XPRT_CLOSING, &xprt->state);
 	smp_mb__after_clear_bit();
@@ -1515,8 +1527,8 @@ static void xs_tcp_state_change(struct sock *sk)
 		break;
 	case TCP_CLOSE_WAIT:
 		/* The server initiated a shutdown of the socket */
-		xprt_force_disconnect(xprt);
 		xprt->connect_cookie++;
+		xs_tcp_force_close(xprt);
 	case TCP_CLOSING:
 		/*
 		 * If the server closed down the connection, make sure that
@@ -2159,8 +2171,7 @@ static void xs_tcp_setup_socket(struct work_struct *work)
 		/* We're probably in TIME_WAIT. Get rid of existing socket,
 		 * and retry
 		 */
-		set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
-		xprt_force_disconnect(xprt);
+		xs_tcp_force_close(xprt);
 		break;
 	case -ECONNREFUSED:
 	case -ECONNRESET:
--
1.7.9.5