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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 9F10DC433ED for ; Wed, 21 Apr 2021 14:19:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 499686144E for ; Wed, 21 Apr 2021 14:19:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239765AbhDUOUI (ORCPT ); Wed, 21 Apr 2021 10:20:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:48714 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243495AbhDUOTu (ORCPT ); Wed, 21 Apr 2021 10:19:50 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 55AC961451; Wed, 21 Apr 2021 14:19:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1619014757; bh=bBmIn8S8ZMIPvTWH/+ochcCoeMONUXeO4WBQU2iFBEg=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=lqYc8BHKKR3M22tT1kNQkEdfvRhiIOKEdI2dF1DWl1QGd1sDoCBc0MVeAalheZ46m hJyjhy1ad3X/RmGWZWWkByEpqMDCDiFvS+x7CZRhAo9CHx3u4x94aTOqdavs3aX7B8 Dp6bFxCEbWdR9xWmjhnVGzxocghVJtTjQ3k7bEayS5Pnbnx42CbkxWQxXxXS/Gl7MP zfrJhblRLM/QvoPePtJWaHm0NpjFsCNlHAHZ2tFczlScD2dM/hrPLOU/0EI2lK0Cqb Kr/4/K6e18mbn5S7dvGC17psQDlTx7F+3Q2gX7h7Y4gbwZ2Fkia+L9lU9DadcC2km/ cBoOX1FxQGaqw== Received: by mail-ej1-f50.google.com with SMTP id v6so62457021ejo.6; Wed, 21 Apr 2021 07:19:17 -0700 (PDT) X-Gm-Message-State: AOAM530z9rfTcwsdJOZiZm06SvfYSpwaYvE3yNwtEqXF1AEC+0VK1K4D olu+mx61qlQfjXfMmBYE6dOjrOklxAolvW6oWro= X-Google-Smtp-Source: ABdhPJxaQljIkxFOGY7dNHi0Pk8uTSoPpwsWKcSgA3QnPpgl9pl/W9LzYtSuU+JlWOvBgBy/wcAMfxpFNn+mSdq30Qs= X-Received: by 2002:a17:906:4e93:: with SMTP id v19mr32427309eju.215.1619014755832; Wed, 21 Apr 2021 07:19:15 -0700 (PDT) MIME-Version: 1.0 References: <20210407000913.2207831-1-pakki001@umn.edu> In-Reply-To: From: Krzysztof Kozlowski Date: Wed, 21 Apr 2021 16:19:03 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] net/rds: Avoid potential use after free in rds_send_remove_from_sock To: Leon Romanovsky , "David S. Miller" Cc: Jakub Kicinski , Aditya Pakki , Santosh Shilimkar , netdev@vger.kernel.org, linux-rdma@vger.kernel.org, rds-devel@oss.oracle.com, "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Tue, 20 Apr 2021 at 11:13, Leon Romanovsky wrote: > > On Tue, Apr 20, 2021 at 12:09:06PM +0300, Leon Romanovsky wrote: > > On Tue, Apr 06, 2021 at 07:09:12PM -0500, Aditya Pakki wrote: > > > In case of rs failure in rds_send_remove_from_sock(), the 'rm' resource > > > is freed and later under spinlock, causing potential use-after-free. > > > Set the free pointer to NULL to avoid undefined behavior. > > > > > > Signed-off-by: Aditya Pakki > > > --- > > > net/rds/message.c | 1 + > > > net/rds/send.c | 2 +- > > > 2 files changed, 2 insertions(+), 1 deletion(-) > > > > Dave, Jakub > > > > Please revert this patch, given responses from Eric and Al together > > with this response from Greg here https://lore.kernel.org/lkml/YH5/i7OvsjSmqADv@kroah.com > > https://lore.kernel.org/lkml/YH5%2Fi7OvsjSmqADv@kroah.com/ > > > > > BTW, I looked on the rds code too and agree with Eric, this patch > > is a total garbage. When reverting, consider giving credits to Kees/Coverity as he pointed out after testing linux-next that this is bogus: https://lore.kernel.org/linux-next/202104081640.1A09A99900@keescook/ Best regards, Krzysztof