From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6CB7C43215 for ; Wed, 13 Nov 2019 19:48:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3130B206ED for ; Wed, 13 Nov 2019 19:48:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726969AbfKMTsG (ORCPT ); Wed, 13 Nov 2019 14:48:06 -0500 Received: from smtp.uniroma2.it ([160.80.6.16]:57695 "EHLO smtp.uniroma2.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726120AbfKMTsF (ORCPT ); Wed, 13 Nov 2019 14:48:05 -0500 X-Greylist: delayed 1019 seconds by postgrey-1.27 at vger.kernel.org; Wed, 13 Nov 2019 14:47:58 EST Received: from localhost.localdomain ([160.80.103.126]) by smtp-2015.uniroma2.it (8.14.4/8.14.4/Debian-8) with ESMTP id xADJTiml023525 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Wed, 13 Nov 2019 20:30:27 +0100 From: Andrea Mayer To: "David S. Miller" , Alexey Kuznetsov , Hideaki YOSHIFUJI , David Lebrun , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Andrea Mayer Subject: [net-next, 1/3] seg6: verify srh pointer in get_srh() Date: Wed, 13 Nov 2019 20:29:10 +0100 Message-Id: <20191113192912.17546-2-andrea.mayer@uniroma2.it> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191113192912.17546-1-andrea.mayer@uniroma2.it> References: <20191113192912.17546-1-andrea.mayer@uniroma2.it> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Virus-Scanned: clamav-milter 0.100.0 at smtp-2015 X-Virus-Status: Clean Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org pskb_may_pull may change pointers in header. For this reason, it is mandatory to reload any pointer that points into skb header. Signed-off-by: Andrea Mayer --- net/ipv6/seg6_local.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c index 9d4f75e0d33a..e187dec2eed1 100644 --- a/net/ipv6/seg6_local.c +++ b/net/ipv6/seg6_local.c @@ -75,12 +75,16 @@ static struct ipv6_sr_hdr *get_srh(struct sk_buff *skb) return NULL; srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); - len = (srh->hdrlen + 1) << 3; if (!pskb_may_pull(skb, srhoff + len)) return NULL; + /* note that pskb_may_pull may change pointers in header; + * for this reason it is necessary to reload them when needed. + */ + srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); + if (!seg6_validate_srh(srh, len)) return NULL; -- 2.20.1