Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751744AbcDRDsX (ORCPT ); Sun, 17 Apr 2016 23:48:23 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:35332 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751900AbcDRC0m (ORCPT ); Sun, 17 Apr 2016 22:26:42 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Florian Westphal , "David S. Miller" Subject: [PATCH 3.14 11/37] ipv6: re-enable fragment header matching in ipv6_find_hdr Date: Mon, 18 Apr 2016 11:25:43 +0900 Message-Id: <20160418022401.286934244@linuxfoundation.org> X-Mailer: git-send-email 2.8.0 In-Reply-To: <20160418022400.661946311@linuxfoundation.org> References: <20160418022400.661946311@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 Content-Length: 1543 Lines: 47 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Florian Westphal [ Upstream commit 5d150a985520bbe3cb2aa1ceef24a7e32f20c15f ] 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: Greg Kroah-Hartman --- net/ipv6/exthdrs_core.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/net/ipv6/exthdrs_core.c +++ b/net/ipv6/exthdrs_core.c @@ -257,7 +257,11 @@ int ipv6_find_hdr(const struct sk_buff * *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) {