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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 893DAC433DF for ; Wed, 20 May 2020 00:10:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 57BC8207C4 for ; Wed, 20 May 2020 00:10:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="LVb/LnYE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727029AbgETAKr (ORCPT ); Tue, 19 May 2020 20:10:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35220 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726348AbgETAKr (ORCPT ); Tue, 19 May 2020 20:10:47 -0400 Received: from mail-qv1-xf43.google.com (mail-qv1-xf43.google.com [IPv6:2607:f8b0:4864:20::f43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7D34C061A0E for ; Tue, 19 May 2020 17:10:46 -0700 (PDT) Received: by mail-qv1-xf43.google.com with SMTP id fb16so547531qvb.5 for ; Tue, 19 May 2020 17:10:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=1nnNMMnWgVyddSvx9CTHRp85r+Uj2T/EgMi8iim52iY=; b=LVb/LnYEoZe/hqO2/o5y+SCwpWFlcD/OzI++bhVo7RKZq90uUz9gmoGH+/45X+MDte 9Itf5OW4Cc0+8iNIsEp9QldXccLCYOOXxe57Sm1cHCDdjlfkgY+6MWzPqdPE0N5W6sVJ UngYpYZ+SFTMFjtCSYMyEMMwIJffklZXje5JNDyn8tYKYQ9YG5zlcqBdqHOfU0oQ9Uw9 sXxDcISZGRbopbiyyH/7otZAIWj0g9hDoVNxGs8EVQgDkvbjYdF0GJMDl1atusMM+kci maK30q1hgpUahvg+JY+rRdll417il1WAMpgiGnih61Jo9t2HhRiV5twbf75SYKTXX2NG LrQg== 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:user-agent; bh=1nnNMMnWgVyddSvx9CTHRp85r+Uj2T/EgMi8iim52iY=; b=LyNQBZt3z+WwNWjeYzNl1ffG2qm/V0TstuBDZc1ewJNUq0NLmAPGD5ig0LtxRGMpvF ik3y2U1Ckt/Gez6ord9h+uMpAY6e/nNFeSwRHR/szS8EpgWJpc77GwdcLhhOG5ccfkyB 1stMEdmW9OezHZkt3B0mSoY18m/I+KlHoRrgKDnKB6oYK9HiUg5XP8lJQI3CfxEEM4Y7 9cqHw0r2x/GYurXrhVsfPm2rg+HhwbwBckVrLNR5xX5RXxZyNuaQaa2+OcF7K4gE9JWJ aZLpzXwaLMHqbOXHV3H7VUSo7zZU7tF6t6J4ILQOGNZCUaWrcmUjWnye92aIQGDoiaw5 ODNQ== X-Gm-Message-State: AOAM531Rk4WCs0VYn+Ul9fQ4My3IT8dl46SAv4BAgB1lSAh9AJmFapTg pZf7gXdGthcboLJXuCCwVelZKg== X-Google-Smtp-Source: ABdhPJwsz5AKr0aQtHN738xGZhJMASG0JaA7L/CXolhH1cBCNFuWAt77YF/YQI1M6dbZTVO5OtyTrQ== X-Received: by 2002:a05:6214:42f:: with SMTP id a15mr2302980qvy.170.1589933446165; Tue, 19 May 2020 17:10:46 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-156-34-48-30.dhcp-dynamic.fibreop.ns.bellaliant.net. [156.34.48.30]) by smtp.gmail.com with ESMTPSA id d196sm959328qkg.16.2020.05.19.17.10.45 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Tue, 19 May 2020 17:10:45 -0700 (PDT) Received: from jgg by mlx.ziepe.ca with local (Exim 4.90_1) (envelope-from ) id 1jbCJp-0003It-Am; Tue, 19 May 2020 21:10:45 -0300 Date: Tue, 19 May 2020 21:10:45 -0300 From: Jason Gunthorpe To: Divya Indi Cc: linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, Kaike Wan , Gerd Rausch , =?utf-8?B?SMOla29u?= Bugge , Srinivas Eeda , Rama Nichanamatlu , Doug Ledford Subject: Re: [PATCH 1/2] IB/sa: Resolving use-after-free in ib_nl_send_msg. Message-ID: <20200520001045.GA31189@ziepe.ca> References: <1588876487-5781-1-git-send-email-divya.indi@oracle.com> <1588876487-5781-2-git-send-email-divya.indi@oracle.com> <20200508000809.GM26002@ziepe.ca> <33fc99e2-e9fc-3c8c-e47f-41535f514c2d@oracle.com> <20200513150021.GD29989@ziepe.ca> <272dbe83-a72b-d38b-6993-d3bbda50a7d1@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <272dbe83-a72b-d38b-6993-d3bbda50a7d1@oracle.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Tue, May 19, 2020 at 04:30:52PM -0700, Divya Indi wrote: > Hi Jason, > > I wanted to follow up to see if you got a chance to review the following reply? Not yet, it still seems bad to be doing code like this. If two threads are sharing memory they really need to use a refcount/kref not rely on some sketchy thing with flags. It is very hard to tell if the sketchy thing with flags is correct or not. Jason