From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965059AbcATWIA (ORCPT ); Wed, 20 Jan 2016 17:08:00 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:40163 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935126AbcATWBn (ORCPT ); Wed, 20 Jan 2016 17:01:43 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Vyukov , Eric Dumazet , Vlad Yasevich , "David S. Miller" Subject: [PATCH 3.14 36/47] ipv6: sctp: clone options to avoid use after free Date: Wed, 20 Jan 2016 14:01:08 -0800 Message-Id: <20160120215513.034122658@linuxfoundation.org> X-Mailer: git-send-email 2.7.0 In-Reply-To: <20160120215507.575738941@linuxfoundation.org> References: <20160120215507.575738941@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 9470e24f35ab81574da54e69df90c1eb4a96b43f ] SCTP is lacking proper np->opt cloning at accept() time. TCP and DCCP use ipv6_dup_options() helper, do the same in SCTP. We might later factorize this code in a common helper to avoid future mistakes. Reported-by: Dmitry Vyukov Signed-off-by: Eric Dumazet Acked-by: Vlad Yasevich Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/ipv6.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -638,6 +638,7 @@ static struct sock *sctp_v6_create_accep struct sock *newsk; struct ipv6_pinfo *newnp, *np = inet6_sk(sk); struct sctp6_sock *newsctp6sk; + struct ipv6_txoptions *opt; newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot); if (!newsk) @@ -657,6 +658,13 @@ static struct sock *sctp_v6_create_accep memcpy(newnp, np, sizeof(struct ipv6_pinfo)); + rcu_read_lock(); + opt = rcu_dereference(np->opt); + if (opt) + opt = ipv6_dup_options(newsk, opt); + RCU_INIT_POINTER(newnp->opt, opt); + rcu_read_unlock(); + /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() * and getpeername(). */