From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753997AbcAETtX (ORCPT ); Tue, 5 Jan 2016 14:49:23 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:45628 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753132AbcAETtQ (ORCPT ); Tue, 5 Jan 2016 14:49:16 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Eric Dumazet , "David S. Miller" , Kamal Mostafa Subject: [PATCH 4.2.y-ckt 191/211] ipv6: sctp: clone options to avoid use after free Date: Tue, 5 Jan 2016 11:44:59 -0800 Message-Id: <1452023119-25647-192-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1452023119-25647-1-git-send-email-kamal@canonical.com> References: <1452023119-25647-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 4.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.2.8-ckt1 -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: Kamal Mostafa --- net/sctp/ipv6.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c index e917d27..40677cf 100644 --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -635,6 +635,7 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 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, 0); if (!newsk) @@ -654,6 +655,13 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 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(). */ -- 1.9.1