From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758662Ab2KVWow (ORCPT ); Thu, 22 Nov 2012 17:44:52 -0500 Received: from mail.kernel.org ([198.145.19.201]:49015 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753451Ab2KVSdf (ORCPT ); Thu, 22 Nov 2012 13:33:35 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, "Yan, Zheng" , Sage Weil Subject: [ 167/171] ceph: Fix oops when handling mdsmap that decreases max_mds Date: Wed, 21 Nov 2012 16:41:53 -0800 Message-Id: <20121122004050.103315082@linuxfoundation.org> X-Mailer: git-send-email 1.8.0.197.g5a90748 In-Reply-To: <20121122004033.298367941@linuxfoundation.org> References: <20121122004033.298367941@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Yan, Zheng" (cherry picked from commit 3e8f43a089f06279c5f76a9ccd42578eebf7bfa5) When i >= newmap->m_max_mds, ceph_mdsmap_get_addr(newmap, i) return NULL. Passing NULL to memcmp() triggers oops. Signed-off-by: Yan, Zheng Signed-off-by: Sage Weil Signed-off-by: Greg Kroah-Hartman --- fs/ceph/mds_client.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -2634,7 +2634,8 @@ static void check_new_map(struct ceph_md ceph_mdsmap_is_laggy(newmap, i) ? " (laggy)" : "", session_state_name(s->s_state)); - if (memcmp(ceph_mdsmap_get_addr(oldmap, i), + if (i >= newmap->m_max_mds || + memcmp(ceph_mdsmap_get_addr(oldmap, i), ceph_mdsmap_get_addr(newmap, i), sizeof(struct ceph_entity_addr))) { if (s->s_state == CEPH_MDS_SESSION_OPENING) {