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 34547C433EF for ; Fri, 11 Mar 2022 22:45:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229588AbiCKWq7 (ORCPT ); Fri, 11 Mar 2022 17:46:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49032 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229591AbiCKWqp (ORCPT ); Fri, 11 Mar 2022 17:46:45 -0500 Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [IPv6:2607:f8b0:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 64C662213B1; Fri, 11 Mar 2022 14:21:56 -0800 (PST) Received: by mail-pf1-x42b.google.com with SMTP id s8so9010121pfk.12; Fri, 11 Mar 2022 14:21:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:message-id:in-reply-to:references:subject :mime-version:content-transfer-encoding; bh=LmW5vUK9KoRLxo/PSGb5rbV+ARklvHlsTha23hQR9mw=; b=KBFsvFgNVvZ+1ywMkytegzF6la0bukQWFV5x89J3kZhsqJZxFBqL0L08qW+/KnGbgq 6mATpGXcQVYg9aB0ZodzSUPIQrQFF/6pTuV1C73gCAY9kKxcddjg3p3Nm3Ur/s3ferwF ZWh//SycJtJjytkHlj0AjKad+U8JNLxb1I7g6qEXQ+J52tPLQhLeUxyLX3ncuh/6cXHh 3Pxlv2cwVaPJvta9wFeOWfxxrWmexlk+eStnlQR/zjGcCXD+QYi7zNhIy8J1l1/1TK95 Yu4oaGuzq6qN/gOcxz7wSmuROM9X0c1Ioob15cLHH5sONS+q/j6a1r9WRjAiT3ul59KK gJJw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:message-id:in-reply-to :references:subject:mime-version:content-transfer-encoding; bh=LmW5vUK9KoRLxo/PSGb5rbV+ARklvHlsTha23hQR9mw=; b=jywrrvjHuVh4PCuEyY5zsyjoZIzjiemD9SSJcuhnDRlgfyHo1BIkqF8/48Id32Sp2J rd+FEz9ZK2DujtrJhXIKnI/KEoz4pEqyBH2C0J4pWsyhXuTpE9Qz64Q4le1eQ3qjHxp9 FjJm7XY1PNxWiuh3dNfkMlw043PDOdIbY76xaXrkdhK3owTjoOYXTyoblm3bXNQpNCIH +faH+LRLJYzdohL+gB0TAQ9OOzTThlj7OCvi6Kr6kPWPBeNG7VQjicdy1mJ0bDOYfmcf buUDncuupzhoXhg6ZNgk/ISqNeqrkMt6zqyTjnopPkiqHqa8inp3uDpNZbzoVmXi7TSt nDIg== X-Gm-Message-State: AOAM5337BJvA8akUuju0GrX1BquMl8LbYSemhlM7x9tg3k299DzwyBDe 8m/ICCNq34IEkJM363HqBOqtpdkCbGJ4VQ== X-Google-Smtp-Source: ABdhPJwY46nvb/RvNPd6oa4/pmc9J3ZRlYiPiAzxIuOoQ2ZWNwZLtgWeajQ/W2MBKSGZJXbfMJnEeg== X-Received: by 2002:a05:6e02:188d:b0:2c6:70cd:2d66 with SMTP id o13-20020a056e02188d00b002c670cd2d66mr9666327ilu.36.1647035510364; Fri, 11 Mar 2022 13:51:50 -0800 (PST) Received: from localhost ([99.197.200.79]) by smtp.gmail.com with ESMTPSA id q9-20020a5edb09000000b00645c7a00cbbsm4590572iop.20.2022.03.11.13.51.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 11 Mar 2022 13:51:50 -0800 (PST) Date: Fri, 11 Mar 2022 13:51:41 -0800 From: John Fastabend To: Wang Yufen , john.fastabend@gmail.com, daniel@iogearbox.net, jakub@cloudflare.com, lmb@cloudflare.com, davem@davemloft.net, bpf@vger.kernel.org Cc: edumazet@google.com, yoshfuji@linux-ipv6.org, dsahern@kernel.org, kuba@kernel.org, ast@kernel.org, andrii@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, kpsingh@kernel.org, netdev@vger.kernel.org, Wang Yufen Message-ID: <622bc46dafb12_8327a2081f@john.notmuch> In-Reply-To: <20220304081145.2037182-5-wangyufen@huawei.com> References: <20220304081145.2037182-1-wangyufen@huawei.com> <20220304081145.2037182-5-wangyufen@huawei.com> Subject: RE: [PATCH bpf-next v3 4/4] bpf, sockmap: Fix double uncharge the mem of sk_msg Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Wang Yufen wrote: > If tcp_bpf_sendmsg is running during a tear down operation, psock may be > freed. > > tcp_bpf_sendmsg() > tcp_bpf_send_verdict() > sk_msg_return() > tcp_bpf_sendmsg_redir() > unlikely(!psock)) > sk_msg_free() > > The mem of msg has been uncharged in tcp_bpf_send_verdict() by > sk_msg_return(), and would be uncharged by sk_msg_free() again. When psock > is null, we can simply returning an error code, this would then trigger > the sk_msg_free_nocharge in the error path of __SK_REDIRECT and would have > the side effect of throwing an error up to user space. This would be a > slight change in behavior from user side but would look the same as an > error if the redirect on the socket threw an error. > > This issue can cause the following info: > WARNING: CPU: 0 PID: 2136 at net/ipv4/af_inet.c:155 inet_sock_destruct+0x13c/0x260 > Call Trace: > > __sk_destruct+0x24/0x1f0 > sk_psock_destroy+0x19b/0x1c0 > process_one_work+0x1b3/0x3c0 > worker_thread+0x30/0x350 > ? process_one_work+0x3c0/0x3c0 > kthread+0xe6/0x110 > ? kthread_complete_and_exit+0x20/0x20 > ret_from_fork+0x22/0x30 > > > Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") > Signed-off-by: Wang Yufen > --- > net/ipv4/tcp_bpf.c | 7 +++---- > 1 file changed, 3 insertions(+), 4 deletions(-) Thanks John! Acked-by: John Fastabend