From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C5561C43381 for ; Thu, 21 Feb 2019 14:38:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9522B20838 for ; Thu, 21 Feb 2019 14:38:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550759902; bh=VYH3E6CRqYttHLeF+a9LqThk/QVZjpzFvwozRVUrVU8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=lva5xg1MrBYjhJWZIPNcoNBk4zGrTaCmFtl0c+iz7CiN2IbQB4nh7SGp851DoH++d vuisoLvx5gapwKZgz3A9UhmzOogyIbug+W9PMBUJLVrwCNYV0nX+w2yfqbXvzxIIcd ceV/VTH71y7xJDv+Z8y1OsvP9Z2jykWE7LnmZDSY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728656AbfBUOiV (ORCPT ); Thu, 21 Feb 2019 09:38:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:60000 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728643AbfBUOiS (ORCPT ); Thu, 21 Feb 2019 09:38:18 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 89C062075C; Thu, 21 Feb 2019 14:38:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550759898; bh=VYH3E6CRqYttHLeF+a9LqThk/QVZjpzFvwozRVUrVU8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=grUlXTAI5FSyxDsgGMFw+rumYU57u2tQJ4HArTvi94QZJSZQ2ppmO19Xj27UaX8Ul iHuM4KTMIgdk5bVd/CbmBsjChWbgH+eLHEUxb4hwIzc5RJibNlH/vuGWiyUk//9NjB 3z/rZrSNYyrRz0a94tEdg7SoXKV4xky161bgPXms= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , soukjin bae , Neal Cardwell , "David S. Miller" Subject: [PATCH 4.4 09/20] tcp: clear icsk_backoff in tcp_write_queue_purge() Date: Thu, 21 Feb 2019 15:35:39 +0100 Message-Id: <20190221141947.039775713@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190221141946.772985220@linuxfoundation.org> References: <20190221141946.772985220@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 04c03114be82194d4a4858d41dba8e286ad1787c ] soukjin bae reported a crash in tcp_v4_err() handling ICMP_DEST_UNREACH after tcp_write_queue_head(sk) returned a NULL pointer. Current logic should have prevented this : if (seq != tp->snd_una || !icsk->icsk_retransmits || !icsk->icsk_backoff || fastopen) break; Problem is the write queue might have been purged and icsk_backoff has not been cleared. Signed-off-by: Eric Dumazet Reported-by: soukjin bae Acked-by: Neal Cardwell Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/net/tcp.h | 1 + net/ipv4/tcp.c | 1 - 2 files changed, 1 insertion(+), 1 deletion(-) --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1457,6 +1457,7 @@ static inline void tcp_write_queue_purge sk_wmem_free_skb(sk, skb); sk_mem_reclaim(sk); tcp_clear_all_retrans_hints(tcp_sk(sk)); + inet_csk(sk)->icsk_backoff = 0; } static inline struct sk_buff *tcp_write_queue_head(const struct sock *sk) --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2253,7 +2253,6 @@ int tcp_disconnect(struct sock *sk, int tp->write_seq += tp->max_window + 2; if (tp->write_seq == 0) tp->write_seq = 1; - icsk->icsk_backoff = 0; tp->snd_cwnd = 2; icsk->icsk_probes_out = 0; tp->packets_out = 0;