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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 AD55CC433DF for ; Mon, 1 Jun 2020 18:43:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92ECC206A4 for ; Mon, 1 Jun 2020 18:43:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731634AbgFASnB (ORCPT ); Mon, 1 Jun 2020 14:43:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728857AbgFASmn (ORCPT ); Mon, 1 Jun 2020 14:42:43 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DF31AC00863E; Mon, 1 Jun 2020 11:34:15 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 477B111D53F8B; Mon, 1 Jun 2020 11:34:15 -0700 (PDT) Date: Mon, 01 Jun 2020 11:34:13 -0700 (PDT) Message-Id: <20200601.113413.1506796443678765558.davem@davemloft.net> To: yuehaibing@huawei.com Cc: jmaloy@redhat.com, ying.xue@windriver.com, kuba@kernel.org, tuong.t.lien@dektech.com.au, netdev@vger.kernel.org, tipc-discussion@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next] tipc: Fix NULL pointer dereference in __tipc_sendstream() From: David Miller In-Reply-To: <20200528143407.56196-1-yuehaibing@huawei.com> References: <20200528143407.56196-1-yuehaibing@huawei.com> X-Mailer: Mew version 6.8 on Emacs 26.3 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Mon, 01 Jun 2020 11:34:15 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: YueHaibing Date: Thu, 28 May 2020 22:34:07 +0800 > tipc_sendstream() may send zero length packet, then tipc_msg_append() > do not alloc skb, skb_peek_tail() will get NULL, msg_set_ack_required > will trigger NULL pointer dereference. > > Reported-by: syzbot+8eac6d030e7807c21d32@syzkaller.appspotmail.com > Fixes: 0a3e060f340d ("tipc: add test for Nagle algorithm effectiveness") > Signed-off-by: YueHaibing Can a TIPC expert please review this? Thank you.