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=-7.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 BF353C2D0E4 for ; Fri, 20 Nov 2020 18:02:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 51F1C2242B for ; Fri, 20 Nov 2020 18:02:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="pfZsxNWB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729250AbgKTSCA (ORCPT ); Fri, 20 Nov 2020 13:02:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36832 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728438AbgKTSCA (ORCPT ); Fri, 20 Nov 2020 13:02:00 -0500 Received: from mail-ej1-x641.google.com (mail-ej1-x641.google.com [IPv6:2a00:1450:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A45A9C0613CF; Fri, 20 Nov 2020 10:01:59 -0800 (PST) Received: by mail-ej1-x641.google.com with SMTP id y17so14044091ejh.11; Fri, 20 Nov 2020 10:01:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=ZHlPDc9Juyz9GO1VkrQBp9QuPjGIDPQ8AofEX/x8Cbo=; b=pfZsxNWBLDC2OuhMxDpD7tpabZcdanHEgvnLCF43ZE6dh4fIq+x6OGl3SqCkivi5X4 kR2sy6XXhA1geH5kNq6X1l5El+YwY0ASFAQVTe3rQT74DOxBjFJOtHiWujhEhYrXSbJs cJ+WJreH8JfTb2Q/aehF/UUzLcxjuqkLQ4aCwtlWDOveYCtIkAvNB+qkWJUb3vUZXgd9 dIbMXpP2XmRzoclTN5WAG7xK0aILXIaMWcQ/ndQPOQbJivC1YI8nAAsg3ZcSun9bVQs4 5FSikJGMnYMo2Cy/Ft7unZUETmSyUJL2B+Ew6iUYww/OBEplu0WsxKrb93VWdeiK4NLT DL1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=ZHlPDc9Juyz9GO1VkrQBp9QuPjGIDPQ8AofEX/x8Cbo=; b=BQeKovkwxjDtZaIgOsnFkH3+26jRurrMnaYkhMmWXMKFSNeAwFp9pLSXYChEj0hzzr rmgyzkQExS8G+jYcnv0o72koqFL0Z1LDhlNvhT+M+W0JL6dDfZXCoYKYZrWXDabJRH+x 7fXM3WKf2+btmUIWWE5yeVoNqW+2APUo57rgUXfMnNAERRvrwd5D4AqMxFWyD2iJRNRE ldtA8LUHm7OFCJQnCg9Bop+d7BMmv5WRMRFDrxtHqZk/EesP8zjZ1KrAPp1WaDjIvMCE lJbnmk2JVXodUHoN0jFyPwwNJpF3W5IaPu/FuIV8AzlaTJIxNYi3fffRulS62H/zm++G FaYA== X-Gm-Message-State: AOAM530Mj3474eOkpuETO446LqTd60uAikMGlOMDGide2h8MyibY8PRx zDGVd59egAYBy+EHr8GZhcE= X-Google-Smtp-Source: ABdhPJzcLHScrILGBpSkLukYGwUpHOE+eU+4Ysaad5rEwj5QtGKsFtJQuoCQ2eZ/UigaTGBq6vM37w== X-Received: by 2002:a17:907:2657:: with SMTP id ar23mr16286661ejc.386.1605895318334; Fri, 20 Nov 2020 10:01:58 -0800 (PST) Received: from skbuf ([188.25.2.177]) by smtp.gmail.com with ESMTPSA id 27sm860119ejy.19.2020.11.20.10.01.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Nov 2020 10:01:54 -0800 (PST) Date: Fri, 20 Nov 2020 20:01:49 +0200 From: Vladimir Oltean To: Christian Eggers Cc: Andrew Lunn , Florian Fainelli , Vivien Didelot , "David S . Miller" , Jakub Kicinski , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next v2] net: dsa: avoid potential use-after-free error Message-ID: <20201120180149.wp4ehikbc2ngvwtf@skbuf> References: <20201119110906.25558-1-ceggers@arri.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201119110906.25558-1-ceggers@arri.de> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 19, 2020 at 12:09:06PM +0100, Christian Eggers wrote: > If dsa_switch_ops::port_txtstamp() returns false, clone will be freed > immediately. Shouldn't store a pointer to freed memory. > > Signed-off-by: Christian Eggers > Fixes: 146d442c2357 ("net: dsa: Keep a pointer to the skb clone for TX timestamping") > --- IMO this is one of the cases to which the following from Documentation/process/stable-kernel-rules.rst does not apply: - It must fix a real bug that bothers people (not a, "This could be a problem..." type thing). Therefore, specifying "net-next" as the target tree here as opposed to "net" is the correct choice. Reviewed-by: Vladimir Oltean Tested-by: Vladimir Oltean