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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,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 0D401C43381 for ; Thu, 21 Feb 2019 14:42:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0B892080D for ; Thu, 21 Feb 2019 14:42:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550760173; bh=mW0u96xWlHL9Rcf2gtxaR12uo9/pclvDz5N7hTwmbas=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UwI+eiTQu5LMZ6JZMYlk8h0mcneGpYu5dGPgi/HgCnxdPPtKpZigRb0wsM//mgqI7 jKniN1p1Gd3lia5jmKdYU8BgcVGfS62UWGXez5ggM7y7Wi3jPUJ0zuXMOHXIfyj4G5 VqtIduGLPhUHk5MOTn4TBaF5MyWmceCmPkEoyzrs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729594AbfBUOmw (ORCPT ); Thu, 21 Feb 2019 09:42:52 -0500 Received: from mail.kernel.org ([198.145.29.99]:38422 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729202AbfBUOms (ORCPT ); Thu, 21 Feb 2019 09:42:48 -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 1EC6D2086A; Thu, 21 Feb 2019 14:42:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550760167; bh=mW0u96xWlHL9Rcf2gtxaR12uo9/pclvDz5N7hTwmbas=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=A536i3rE1aOwULs9TX64H3K7vJEqwofTYyIxgTw6cKBs8zsp2xf3U6xujYNHZVgYG 86r3EU9mzvr3dHBgY//VTXtOiv8B5h4UMSCBc8wLaKRmsR8WYfoxu77Tx2BoUllgvp hcn+JcOiwTNJqzipf2/F6jQ7kfYGu8/sEJTCS7mg= 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" , Sasha Levin Subject: [PATCH 4.20 17/32] tcp: clear icsk_backoff in tcp_write_queue_purge() Date: Thu, 21 Feb 2019 15:36:05 +0100 Message-Id: <20190221125251.884723766@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190221125250.855065214@linuxfoundation.org> References: <20190221125250.855065214@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 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ [ 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: Sasha Levin --- net/ipv4/tcp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 40cbe5609663f..b102973102b9e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2532,6 +2532,7 @@ void tcp_write_queue_purge(struct sock *sk) sk_mem_reclaim(sk); tcp_clear_all_retrans_hints(tcp_sk(sk)); tcp_sk(sk)->packets_out = 0; + inet_csk(sk)->icsk_backoff = 0; } int tcp_disconnect(struct sock *sk, int flags) @@ -2580,7 +2581,6 @@ int tcp_disconnect(struct sock *sk, int flags) 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->snd_ssthresh = TCP_INFINITE_SSTHRESH; -- 2.19.1