Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753675AbcDVLc0 (ORCPT ); Fri, 22 Apr 2016 07:32:26 -0400 Received: from mx2.suse.de ([195.135.220.15]:43950 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752616AbcDVLGN (ORCPT ); Fri, 22 Apr 2016 07:06:13 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Bill Sommerfeld , "David S . Miller" , Jiri Slaby Subject: [PATCH 3.12 23/78] udp6: fix UDP/IPv6 encap resubmit path Date: Fri, 22 Apr 2016 13:05:06 +0200 Message-Id: <64a08e78fa83406a1a9bace07f8de6b104af2068.1461323133.git.jslaby@suse.cz> X-Mailer: git-send-email 2.8.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1513 Lines: 46 From: Bill Sommerfeld 3.12-stable review patch. If anyone has any objections, please let me know. =============== [ Upstream commit 59dca1d8a6725a121dae6c452de0b2611d5865dc ] IPv4 interprets a negative return value from a protocol handler as a request to redispatch to a new protocol. In contrast, IPv6 interprets a negative value as an error, and interprets a positive value as a request for redispatch. UDP for IPv6 was unaware of this difference. Change __udp6_lib_rcv() to return a positive value for redispatch. Note that the socket's encap_rcv hook still needs to return a negative value to request dispatch, and in the case of IPv6 packets, adjust IP6CB(skb)->nhoff to identify the byte containing the next protocol. Signed-off-by: Bill Sommerfeld Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby --- net/ipv6/udp.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 94ca4172b38e..26e1648ca228 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -848,11 +848,9 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, ret = udpv6_queue_rcv_skb(sk, skb); sock_put(sk); - /* a return value > 0 means to resubmit the input, but - * it wants the return to be -protocol, or 0 - */ + /* a return value > 0 means to resubmit the input */ if (ret > 0) - return -ret; + return ret; return 0; } -- 2.8.1