From patchwork Wed Mar 16 20:05:58 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 598752 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 3qQN1L5FjQz9t3V; Thu, 17 Mar 2016 07:11:50 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1agHnH-0001Ha-7g; Wed, 16 Mar 2016 20:11:47 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1agHjL-0007t1-7y for kernel-team@lists.ubuntu.com; Wed, 16 Mar 2016 20:07:43 +0000 Received: from 1.general.kamal.us.vpn ([10.172.68.52] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1agHjK-00085z-PZ; Wed, 16 Mar 2016 20:07:42 +0000 Received: from kamal by fourier with local (Exim 4.86) (envelope-from ) id 1agHjI-0002cL-4F; Wed, 16 Mar 2016 13:07:40 -0700 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.19.y-ckt 65/70] ipv6: re-enable fragment header matching in ipv6_find_hdr Date: Wed, 16 Mar 2016 13:05:58 -0700 Message-Id: <1458158763-9614-66-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1458158763-9614-1-git-send-email-kamal@canonical.com> References: <1458158763-9614-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Cc: Kamal Mostafa , Florian Westphal , "David S . Miller" X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com v3.19.8-ckt17 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Florian Westphal commit 5d150a985520bbe3cb2aa1ceef24a7e32f20c15f upstream. When ipv6_find_hdr is used to find a fragment header (caller specifies target NEXTHDR_FRAGMENT) we erronously return -ENOENT for all fragments with nonzero offset. Before commit 9195bb8e381d, when target was specified, we did not enter the exthdr walk loop as nexthdr == target so this used to work. Now we do (so we can skip empty route headers). When we then stumble upon a frag with nonzero frag_off we must return -ENOENT ("header not found") only if the caller did not specifically request NEXTHDR_FRAGMENT. This allows nfables exthdr expression to match ipv6 fragments, e.g. via nft add rule ip6 filter input frag frag-off gt 0 Fixes: 9195bb8e381d ("ipv6: improve ipv6_find_hdr() to skip empty routing headers") Signed-off-by: Florian Westphal Signed-off-by: David S. Miller Signed-off-by: Kamal Mostafa --- net/ipv6/exthdrs_core.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/ipv6/exthdrs_core.c b/net/ipv6/exthdrs_core.c index 8af3eb5..c7c8f71 100644 --- a/net/ipv6/exthdrs_core.c +++ b/net/ipv6/exthdrs_core.c @@ -257,7 +257,11 @@ int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, *fragoff = _frag_off; return hp->nexthdr; } - return -ENOENT; + if (!found) + return -ENOENT; + if (fragoff) + *fragoff = _frag_off; + break; } hdrlen = 8; } else if (nexthdr == NEXTHDR_AUTH) {