From: Sage Weil <sage@inktank.com>
Date: Fri, 20 Jul 2012 22:34:04 +0000 (-0700)
Subject: libceph: move ceph_con_send() closed check under the con mutex
X-Git-Tag: v3.4.20~25
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5d0f354b3183d005024d43b567335701d928995a;p=platform%2Fkernel%2Flinux-stable.git

libceph: move ceph_con_send() closed check under the con mutex

(cherry picked from commit a59b55a602b6c741052d79c1e3643f8440cddd27)

Take the con mutex before checking whether the connection is closed to
avoid racing with someone else closing it.

Signed-off-by: Sage Weil <sage@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 14d24b7..cb871fc 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -2453,22 +2453,20 @@ static void clear_standby(struct ceph_connection *con)
  */
 void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg)
 {
-	if (test_bit(CLOSED, &con->state)) {
-		dout("con_send %p closed, dropping %p\n", con, msg);
-		ceph_msg_put(msg);
-		return;
-	}
-
 	/* set src+dst */
 	msg->hdr.src = con->msgr->inst.name;
-
 	BUG_ON(msg->front.iov_len != le32_to_cpu(msg->hdr.front_len));
-
 	msg->needs_out_seq = true;
 
-	/* queue */
 	mutex_lock(&con->mutex);
 
+	if (test_bit(CLOSED, &con->state)) {
+		dout("con_send %p closed, dropping %p\n", con, msg);
+		ceph_msg_put(msg);
+		mutex_unlock(&con->mutex);
+		return;
+	}
+
 	BUG_ON(msg->con != NULL);
 	msg->con = con->ops->get(con);
 	BUG_ON(msg->con == NULL);