[ 3.5.yuz extended stable ] Patch "libceph: verify state after retaking con lock after" 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

    libceph: verify state after retaking con lock after

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 9313bb12a82886938bcfd0e852dd42e596613996 Mon Sep 17 00:00:00 2001
From: Sage Weil <sage at inktank.com>
Date: Mon, 30 Jul 2012 18:16:56 -0700
Subject: [PATCH 65/78] libceph: verify state after retaking con lock after
 dispatch

commit 7b862e07b1a4d5c963d19027f10ea78085f27f9b upstream.

We drop the con mutex when delivering a message.  When we retake the
lock, we need to verify we are still in the OPEN state before
preparing to read the next tag, or else we risk stepping on a
connection that has been closed.

Signed-off-by: Sage Weil <sage at inktank.com>
Reviewed-by: Alex Elder <elder at inktank.com>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 net/ceph/messenger.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index a6a0c7a..feb5a2a 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -2003,7 +2003,6 @@ static void process_message(struct ceph_connection *con)
 	con->ops->dispatch(con, msg);

 	mutex_lock(&con->mutex);
-	prepare_read_tag(con);
 }


@@ -2213,6 +2212,8 @@ more:
 		if (con->in_tag == CEPH_MSGR_TAG_READY)
 			goto more;
 		process_message(con);
+		if (con->state == CON_STATE_OPEN)
+			prepare_read_tag(con);
 		goto more;
 	}
 	if (con->in_tag == CEPH_MSGR_TAG_ACK) {
--
1.7.9.5