Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753651AbdHIRIy (ORCPT ); Wed, 9 Aug 2017 13:08:54 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:39212 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753981AbdHIQyb (ORCPT ); Wed, 9 Aug 2017 12:54:31 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xin Long , "David S. Miller" Subject: [PATCH 4.12 058/106] sctp: fix an array overflow when all ext chunks are set Date: Wed, 9 Aug 2017 09:52:42 -0700 Message-Id: <20170809164524.635891716@linuxfoundation.org> X-Mailer: git-send-email 2.14.0 In-Reply-To: <20170809164515.714288642@linuxfoundation.org> References: <20170809164515.714288642@linuxfoundation.org> User-Agent: quilt/0.65 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 Content-Length: 1673 Lines: 50 4.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long [ Upstream commit 10b3bf54406bb7f4e78da9bb2a485c5c986678ad ] Marcelo noticed an array overflow caused by commit c28445c3cb07 ("sctp: add reconf_enable in asoc ep and netns"), in which sctp would add SCTP_CID_RECONF into extensions when reconf_enable is set in sctp_make_init and sctp_make_init_ack. Then now when all ext chunks are set, 4 ext chunk ids can be put into extensions array while extensions array size is 3. It would cause a kernel panic because of this overflow. This patch is to fix it by defining extensions array size is 4 in both sctp_make_init and sctp_make_init_ack. Fixes: c28445c3cb07 ("sctp: add reconf_enable in asoc ep and netns") Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/sm_make_chunk.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -228,7 +228,7 @@ struct sctp_chunk *sctp_make_init(const sctp_adaptation_ind_param_t aiparam; sctp_supported_ext_param_t ext_param; int num_ext = 0; - __u8 extensions[3]; + __u8 extensions[4]; sctp_paramhdr_t *auth_chunks = NULL, *auth_hmacs = NULL; @@ -396,7 +396,7 @@ struct sctp_chunk *sctp_make_init_ack(co sctp_adaptation_ind_param_t aiparam; sctp_supported_ext_param_t ext_param; int num_ext = 0; - __u8 extensions[3]; + __u8 extensions[4]; sctp_paramhdr_t *auth_chunks = NULL, *auth_hmacs = NULL, *auth_random = NULL;