From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932726Ab2JAXAo (ORCPT ); Mon, 1 Oct 2012 19:00:44 -0400 Received: from 1wt.eu ([62.212.114.60]:35195 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932683Ab2JAXAi (ORCPT ); Mon, 1 Oct 2012 19:00:38 -0400 Message-Id: <20121001225200.909225352@1wt.eu> User-Agent: quilt/0.48-1 Date: Tue, 02 Oct 2012 00:53:15 +0200 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , "David S. Miller" , Greg Kroah-Hartman , Willy Tarreau Subject: [ 078/180] net: fix a race in sock_queue_err_skb() In-Reply-To: <6a854f579a99b4fe2efaca1057e8ae22@local> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 110c43304db6f06490961529536c362d9ac5732f ] As soon as an skb is queued into socket error queue, another thread can consume it, so we are not allowed to reference skb anymore, or risk use after free. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman Signed-off-by: Willy Tarreau --- net/core/skbuff.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 025f924..72ff527 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2989,6 +2989,8 @@ static void sock_rmem_free(struct sk_buff *skb) */ int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb) { + int len = skb->len; + if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= (unsigned)sk->sk_rcvbuf) return -ENOMEM; @@ -3000,7 +3002,7 @@ int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb) skb_queue_tail(&sk->sk_error_queue, skb); if (!sock_flag(sk, SOCK_DEAD)) - sk->sk_data_ready(sk, skb->len); + sk->sk_data_ready(sk, len); return 0; } EXPORT_SYMBOL(sock_queue_err_skb); -- 1.7.2.1.45.g54fbc