Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933328Ab2KZRIx (ORCPT ); Mon, 26 Nov 2012 12:08:53 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:47659 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933280Ab2KZRIk (ORCPT ); Mon, 26 Nov 2012 12:08:40 -0500 From: Herton Ronaldo Krzesinski To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Sage Weil , Herton Ronaldo Krzesinski Subject: [PATCH 141/270] libceph: recheck con state after allocating incoming message Date: Mon, 26 Nov 2012 14:57:11 -0200 Message-Id: <1353949160-26803-142-git-send-email-herton.krzesinski@canonical.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1353949160-26803-1-git-send-email-herton.krzesinski@canonical.com> References: <1353949160-26803-1-git-send-email-herton.krzesinski@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1723 Lines: 51 3.5.7u1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Sage Weil commit 6139919133377652992a5fe134e22abce3e9c25e upstream. We drop the lock when calling the ->alloc_msg() con op, which means we need to (a) not clobber con->in_msg without the mutex held, and (b) we need to verify that we are still in the OPEN state when we retake it to avoid causing any mayhem. If the state does change, -EAGAIN will get us back to con_work() and loop. Signed-off-by: Sage Weil Reviewed-by: Alex Elder Signed-off-by: Herton Ronaldo Krzesinski --- net/ceph/messenger.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index 13b549b..b6655b1 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -2735,9 +2735,16 @@ static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip) BUG_ON(con->in_msg != NULL); if (con->ops->alloc_msg) { + struct ceph_msg *msg; + mutex_unlock(&con->mutex); - con->in_msg = con->ops->alloc_msg(con, hdr, skip); + msg = con->ops->alloc_msg(con, hdr, skip); mutex_lock(&con->mutex); + if (con->state != CON_STATE_OPEN) { + ceph_msg_put(msg); + return -EAGAIN; + } + con->in_msg = msg; if (con->in_msg) { con->in_msg->con = con->ops->get(con); BUG_ON(con->in_msg->con == NULL); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/