From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 38793 invoked by alias); 15 Nov 2016 19:35:19 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 38700 invoked by uid 89); 15 Nov 2016 19:35:18 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-4.5 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 spammy=won X-HELO: zimbra.cs.ucla.edu Subject: Re: [PATCH 0/3] explicit_bzero v5 To: Zack Weinberg , Florian Weimer References: <20161115155509.12692-1-zackw@panix.com> <677c23f1-d10a-890d-b875-039d32a3d228@cs.ucla.edu> <03bf455b-7dc9-663b-a748-8f1da9cfcfd3@cs.ucla.edu> <388972da-c60c-6314-b39d-db5fc818fdb8@redhat.com> Cc: GNU C Library , Carlos O'Donell , "Michael Kerrisk (man-pages)" From: Paul Eggert Message-ID: Date: Tue, 15 Nov 2016 19:35:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2016-11/txt/msg00509.txt.bz2 On 11/15/2016 10:54 AM, Zack Weinberg wrote: > If the adversary can read the stack at all, I suspect they've already > won, no matter what we do. That will likely be true in many applications, but not in all. It's worth documenting the issue for applications that put sensitive objects in the heap, as they might not expose these object addresses to the stack now, but could do so if modified to invoke explicit_bzero.