From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932542Ab1DYUbo (ORCPT ); Mon, 25 Apr 2011 16:31:44 -0400 Received: from 1wt.eu ([62.212.114.60]:34596 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932455Ab1DYUZ0 (ORCPT ); Mon, 25 Apr 2011 16:25:26 -0400 Message-Id: <20110425200240.468187050@pcw.home.local> User-Agent: quilt/0.48-1 Date: Mon, 25 Apr 2011 22:05:24 +0200 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@kernel.org, stable-review@kernel.org Cc: "Steven J. Magnani" , "David S. Miller" Subject: [PATCH 172/173] net: Fix oops from tcp_collapse() when using splice() In-Reply-To: <46075c3a3ef08be6d70339617d6afc98@local> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27.59-stable review patch. If anyone has any objections, please let us know. ------------------ From: Steven J. Magnani commit baff42ab1494528907bf4d5870359e31711746ae upstream. tcp_read_sock() can have a eat skbs without immediately advancing copied_seq. This can cause a panic in tcp_collapse() if it is called as a result of the recv_actor dropping the socket lock. A userspace program that splices data from a socket to either another socket or to a file can trigger this bug. Signed-off-by: Steven J. Magnani Signed-off-by: David S. Miller diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 6afb6d8..2c75f89 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1368,6 +1368,7 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, sk_eat_skb(sk, skb, 0); if (!desc->count) break; + tp->copied_seq = seq; } tp->copied_seq = seq;