From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967395AbcJFJDW (ORCPT ); Thu, 6 Oct 2016 05:03:22 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:49400 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967029AbcJFJDT (ORCPT ); Thu, 6 Oct 2016 05:03:19 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Erez Shitrit , Leon Romanovsky , Doug Ledford Subject: [PATCH 4.4 76/93] IB/core: Fix use after free in send_leave function Date: Thu, 6 Oct 2016 10:29:46 +0200 Message-Id: <20161006074735.104614229@linuxfoundation.org> X-Mailer: git-send-email 2.10.0 In-Reply-To: <20161006074731.150212126@linuxfoundation.org> References: <20161006074731.150212126@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Erez Shitrit commit 68c6bcdd8bd00394c234b915ab9b97c74104130c upstream. The function send_leave sets the member: group->query_id (group->query_id = ret) after calling the sa_query, but leave_handler can be executed before the setting and it might delete the group object, and will get a memory corruption. Additionally, this patch gets rid of group->query_id variable which is not used. Fixes: faec2f7b96b5 ('IB/sa: Track multicast join/leave requests') Signed-off-by: Erez Shitrit Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/core/multicast.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) --- a/drivers/infiniband/core/multicast.c +++ b/drivers/infiniband/core/multicast.c @@ -106,7 +106,6 @@ struct mcast_group { atomic_t refcount; enum mcast_group_state state; struct ib_sa_query *query; - int query_id; u16 pkey_index; u8 leave_state; int retries; @@ -339,11 +338,7 @@ static int send_join(struct mcast_group member->multicast.comp_mask, 3000, GFP_KERNEL, join_handler, group, &group->query); - if (ret >= 0) { - group->query_id = ret; - ret = 0; - } - return ret; + return (ret > 0) ? 0 : ret; } static int send_leave(struct mcast_group *group, u8 leave_state) @@ -363,11 +358,7 @@ static int send_leave(struct mcast_group IB_SA_MCMEMBER_REC_JOIN_STATE, 3000, GFP_KERNEL, leave_handler, group, &group->query); - if (ret >= 0) { - group->query_id = ret; - ret = 0; - } - return ret; + return (ret > 0) ? 0 : ret; } static void join_group(struct mcast_group *group, struct mcast_member *member,