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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A025CC4332F for ; Thu, 14 Dec 2023 10:57:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1443794AbjLNK50 (ORCPT ); Thu, 14 Dec 2023 05:57:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53360 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1443936AbjLNK5G (ORCPT ); Thu, 14 Dec 2023 05:57:06 -0500 Received: from mail-wm1-x32e.google.com (mail-wm1-x32e.google.com [IPv6:2a00:1450:4864:20::32e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E2911A5; Thu, 14 Dec 2023 02:56:15 -0800 (PST) Received: by mail-wm1-x32e.google.com with SMTP id 5b1f17b1804b1-40c495ab68cso8039605e9.0; Thu, 14 Dec 2023 02:56:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1702551374; x=1703156174; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=7HMfppTjCsAQlZ2a3fZBv4GPzszAAfnmigM/QHv3mPQ=; b=jTYrGmMSfaLXlBYl/j+QVUJAjraIfaPXuVyiu4/0RPBhowah1xIft5/S3EKqhadteg pssvoLa9xZ/Q/bIbw8SCP8UpJW//K4tBvQfBweSH8FePxrXTyjiByCCR41EPi71RdMmK i89BNT9sHjZA3n5GkKi1kYYhz6TMt5vSO1xAf6WPmhh7QavjLJYLtuVqtaumPR+4gcRk M7e012ayBOJyrnbsy2s78uN/eJXbSnTRpji+ir5UDJgpVxY1zlDCMEZYjzHL53Yq0tDX HwgrO3YjV7qPMMRy29xpHNRkPA7yuqB62EQjl5iYxvBVa51CDvtT8wczfrcM3fh48XJJ MWEQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702551374; x=1703156174; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=7HMfppTjCsAQlZ2a3fZBv4GPzszAAfnmigM/QHv3mPQ=; b=vVYHbWkfHF6AzIt0KEyckaykMeFT53cInVgVwOR8eSXOXwDOTpmfoUwRw/ANfsyHTB Qsw44v/6s0ljJj03TaA/ZlHpfniP9t6Qj1jw665U+zPybtUr0BnGSlV+xIIT+8vVKU/S VfTvLItneKUb5/Z7paIfSYOvAHlPSoALhyXvBbSs2gXsXY8qpg/TcMTQ5eugdeTkrosJ 33Hy02WGjzDsRyWDp/0CWzzYoSyV5rO/cR4JTcinUmAlwJfSJyjpOnSf2pahrndQUcsc mPHVqUUjIA6APQOfSkcFUcAZOGEuAHxYHPzT+1dPY5ahWViA9s0YVwcm0+c+qjW98ccU SzZw== X-Gm-Message-State: AOJu0Yx9geqhbduCeXu406rjFiPbOS/HMRzTZED4Cj5rKbjz6KvR/02v hYeGUKKhOYJc7dTxd6gRU40= X-Google-Smtp-Source: AGHT+IFIdfKUeuoCGWCCHDyLxN0ccZ+HYFjDI1/L8FwKokS6fVxdoK9NrtDsArFArTpMzWMbzM5OFg== X-Received: by 2002:a05:600c:1c86:b0:3fe:d637:7b25 with SMTP id k6-20020a05600c1c8600b003fed6377b25mr11633139wms.0.1702551373533; Thu, 14 Dec 2023 02:56:13 -0800 (PST) Received: from [10.0.0.4] ([37.169.173.39]) by smtp.gmail.com with ESMTPSA id f9-20020a7bcd09000000b0040c26a459b4sm1163640wmj.0.2023.12.14.02.56.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 14 Dec 2023 02:56:13 -0800 (PST) Message-ID: <1a97421c-c1f3-4974-ac81-9bc1e224f797@gmail.com> Date: Thu, 14 Dec 2023 11:56:11 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net] net: Return error from sk_stream_wait_connect() if sk_wait_event() fails To: Shigeru Yoshida , davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20231214050922.3480023-1-syoshida@redhat.com> Content-Language: en-US From: Eric Dumazet In-Reply-To: <20231214050922.3480023-1-syoshida@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/14/23 06:09, Shigeru Yoshida wrote: > The following NULL pointer dereference issue occurred: > > BUG: kernel NULL pointer dereference, address: 0000000000000000 > <...> > RIP: 0010:ccid_hc_tx_send_packet net/dccp/ccid.h:166 [inline] > RIP: 0010:dccp_write_xmit+0x49/0x140 net/dccp/output.c:356 > <...> > Call Trace: > > dccp_sendmsg+0x642/0x7e0 net/dccp/proto.c:801 > inet_sendmsg+0x63/0x90 net/ipv4/af_inet.c:846 > sock_sendmsg_nosec net/socket.c:730 [inline] > __sock_sendmsg+0x83/0xe0 net/socket.c:745 > ____sys_sendmsg+0x443/0x510 net/socket.c:2558 > ___sys_sendmsg+0xe5/0x150 net/socket.c:2612 > __sys_sendmsg+0xa6/0x120 net/socket.c:2641 > __do_sys_sendmsg net/socket.c:2650 [inline] > __se_sys_sendmsg net/socket.c:2648 [inline] > __x64_sys_sendmsg+0x45/0x50 net/socket.c:2648 > do_syscall_x64 arch/x86/entry/common.c:51 [inline] > do_syscall_64+0x43/0x110 arch/x86/entry/common.c:82 > entry_SYSCALL_64_after_hwframe+0x63/0x6b > > sk_wait_event() returns an error (-EPIPE) if disconnect() is called on the > socket waiting for the event. However, sk_stream_wait_connect() returns > success, i.e. zero, even if sk_wait_event() returns -EPIPE, so a function > that waits for a connection with sk_stream_wait_connect() may misbehave. > > In the case of the above DCCP issue, dccp_sendmsg() is waiting for the > connection. If disconnect() is called in concurrently, the above issue > occurs. > > This patch fixes the issue by returning error from sk_stream_wait_connect() > if sk_wait_event() fails. > > Fixes: 419ce133ab92 ("tcp: allow again tcp_disconnect() when threads are waiting") > Signed-off-by: Shigeru Yoshida Reviewed-by: Eric Dumazet