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[23.128.96.18]) by mx.google.com with ESMTP id kx1si13020804pjb.26.2022.01.17.03.07.45; Mon, 17 Jan 2022 03:07:57 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20210112 header.b=meug70q8; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236735AbiAQBfX (ORCPT + 99 others); Sun, 16 Jan 2022 20:35:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233906AbiAQBfV (ORCPT ); Sun, 16 Jan 2022 20:35:21 -0500 Received: from mail-pl1-x642.google.com (mail-pl1-x642.google.com [IPv6:2607:f8b0:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5FB41C061574; Sun, 16 Jan 2022 17:35:21 -0800 (PST) Received: by mail-pl1-x642.google.com with SMTP id v2so4586743ply.11; Sun, 16 Jan 2022 17:35:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=yRoTtwlAnLRR60MEEBnO0WsRacU0q0bQ1keqyNzRUO4=; b=meug70q8IUVJ+mG/Y4HyFLhoGiteTRliwby8YcKSPF9495mq1JrDtObgvrT8kH8f6u 9cR1Zqcve5CYkZ8MLnTBWYWaAjZTaGBMn4Xuv3RSas+db2pa3yHNFDv973rbr7QAI6H9 ClkoPL4Ds2bQdxH6IGteb7WxeY/t2njF1JByb98MtZcbYIWhBhpBhTOb2D/lV0V8lTbq 00A1jBdZ1I3D/DI7oWGfTl7YzicgD5hZ2KBEFpC3sqxfE3uB6ql3b0WKef9v/fNkyg9R xN1NUFFNDkhoady+D6Xm7oQUmv3xposCGQWTrolj/T7P7lqm9Qik82D3vUf9Uxa/sH3z Zp1Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=yRoTtwlAnLRR60MEEBnO0WsRacU0q0bQ1keqyNzRUO4=; b=WZTXYhFDfoSqc1OF3AWM692acpi1yqtPDtImE9jAwrVDLb6S7rFJd1ifqWSbqhSO4B oVfU+RaGwniAryxzPJpwLEi4a5xKzU3172sCzNKWoc/INOewZ76bgJPlaSjU+ANb/L0o /DfWWUtgUyetyjpUjlXjsBLEIZHBDa2W/ArESz+rmPOrX3lOn9QpiXQ+l3er2G9G1lq7 9s7lmrCuqUs32Ut+itYC4f9gKSh7odhoEipt1DVt5fZ8d7YQqUuvIZYqMuyz9v2GN2Si q4lNAQXmgQBdhUeWLrzUr+IqmU6yD/GIW5rx7kLajzyfHOUDE/G4rcAOKd/SHTii74hZ TdjQ== X-Gm-Message-State: AOAM532bjrsSCtpPC3Cn5O6gysGAEcn3vMCw5sH3lv4sxJZkhgcGRshY doE5PqJtBNrjIjI7GJ1Knl+7QQLt0exR7wK/ X-Received: by 2002:a17:902:f24a:b0:14a:bc6c:c327 with SMTP id j10-20020a170902f24a00b0014abc6cc327mr2449527plc.24.1642383320757; Sun, 16 Jan 2022 17:35:20 -0800 (PST) Received: from [0.0.0.0] ([209.97.166.32]) by smtp.gmail.com with ESMTPSA id rm11sm784643pjb.54.2022.01.16.17.35.15 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 16 Jan 2022 17:35:20 -0800 (PST) Subject: Re: [PATCH net] ax25: use after free in ax25_connect To: Eric Dumazet , jreuter@yaina.de, ralf@linux-mips.org, davem@davemloft.net, kuba@kernel.org Cc: linux-hams@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220111042048.43532-1-hbh25y@gmail.com> <571c72e8-2111-6aa0-1bd7-e0af7fc50539@gmail.com> <80007b3e-eba8-1fbe-302d-4398830843dd@gmail.com> <8fc4701f-c151-0545-c047-a5df90575d69@gmail.com> From: Hangyu Hua Message-ID: Date: Mon, 17 Jan 2022 09:35:10 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <8fc4701f-c151-0545-c047-a5df90575d69@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I get it. Thanks. On 2022/1/14 下午11:19, Eric Dumazet wrote: > > On 1/13/22 22:54, Hangyu Hua wrote: >> Any suggestions for this patch ? Guys. >> >> I think putting sk_to_ax25 after lock_sock(sk) here will avoid any >> possilbe race conditions like other functions in ax25_proto_ops. CTING) { >> > > As explained, your patch is not needed. > > You failed to describe how a race was possible. > > Just moving code around wont help. > > How about providing a stack trace or some syzbot repro ? >