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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 753DAC2D0DB for ; Tue, 28 Jan 2020 14:26:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C7CF207FD for ; Tue, 28 Jan 2020 14:26:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580221580; bh=9MdhLw8bCOJwhXjVcSWUEJ0OY99eCT6+70jrT5f0DKw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=wfvMUpyG6OkKhIT3OpAXAZoltjIvKqZGxphF/FSI6LYxsFZ9NqNPxKP3/29naJC78 0HVZdhFWJAXBc4PT7GASmJF1PiqXY30Cn4zQUMk5m03ERa+MSCHK7j1VdPOMnznz0l 80CUGZeX89xwhPjKpZ+M3FdYKgpEUlFPkCPljq9U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733175AbgA1O0T (ORCPT ); Tue, 28 Jan 2020 09:26:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:53584 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733159AbgA1O0N (ORCPT ); Tue, 28 Jan 2020 09:26:13 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 58DBD2468D; Tue, 28 Jan 2020 14:26:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580221572; bh=9MdhLw8bCOJwhXjVcSWUEJ0OY99eCT6+70jrT5f0DKw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MUgYEmpGwj8ZUpIxbc3sJ4To0FYD+x8nfmpCb2NsdNkMljafSZy6aCfTCD2nVrrPW 2j6L1A5CLi4puLhUXVsXNuLa+UAg7OwB/bixC5QedMisURPGfZ5vOn8q1BC//wvCDB DFpmeqJasPl54JKw3zKN3LI6mUIlMkxm0oWN8dXs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Martin Schiller , syzbot+429c200ffc8772bfe070@syzkaller.appspotmail.com, syzbot+eec0c87f31a7c3b66f7b@syzkaller.appspotmail.com, "David S. Miller" Subject: [PATCH 4.9 271/271] net/x25: fix nonblocking connect Date: Tue, 28 Jan 2020 15:07:00 +0100 Message-Id: <20200128135912.764322795@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200128135852.449088278@linuxfoundation.org> References: <20200128135852.449088278@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Martin Schiller commit e21dba7a4df4d93da237da65a096084b4f2e87b4 upstream. This patch fixes 2 issues in x25_connect(): 1. It makes absolutely no sense to reset the neighbour and the connection state after a (successful) nonblocking call of x25_connect. This prevents any connection from being established, since the response (call accept) cannot be processed. 2. Any further calls to x25_connect() while a call is pending should simply return, instead of creating new Call Request (on different logical channels). This patch should also fix the "KASAN: null-ptr-deref Write in x25_connect" and "BUG: unable to handle kernel NULL pointer dereference in x25_connect" bugs reported by syzbot. Signed-off-by: Martin Schiller Reported-by: syzbot+429c200ffc8772bfe070@syzkaller.appspotmail.com Reported-by: syzbot+eec0c87f31a7c3b66f7b@syzkaller.appspotmail.com Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/x25/af_x25.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/net/x25/af_x25.c +++ b/net/x25/af_x25.c @@ -764,6 +764,10 @@ static int x25_connect(struct socket *so if (sk->sk_state == TCP_ESTABLISHED) goto out; + rc = -EALREADY; /* Do nothing if call is already in progress */ + if (sk->sk_state == TCP_SYN_SENT) + goto out; + sk->sk_state = TCP_CLOSE; sock->state = SS_UNCONNECTED; @@ -810,7 +814,7 @@ static int x25_connect(struct socket *so /* Now the loop */ rc = -EINPROGRESS; if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) - goto out_put_neigh; + goto out; rc = x25_wait_for_connection_establishment(sk); if (rc)