Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751833AbcCHU73 (ORCPT ); Tue, 8 Mar 2016 15:59:29 -0500 Received: from mail-ob0-f179.google.com ([209.85.214.179]:34632 "EHLO mail-ob0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751519AbcCHU7U (ORCPT ); Tue, 8 Mar 2016 15:59:20 -0500 MIME-Version: 1.0 In-Reply-To: <1457470075-4586-1-git-send-email-sbauer@eng.utah.edu> References: <1457470075-4586-1-git-send-email-sbauer@eng.utah.edu> From: Andy Lutomirski Date: Tue, 8 Mar 2016 12:58:59 -0800 Message-ID: Subject: Re: [PATCH v3 1/3] SROP Mitigation: Architecture independent code for signal cookies To: Scott Bauer Cc: "linux-kernel@vger.kernel.org" , "kernel-hardening@lists.openwall.com" , X86 ML , wmealing@redhat.com, Andi Kleen , Abhiram Balasubramanian Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 513 Lines: 10 On Tue, Mar 8, 2016 at 12:47 PM, Scott Bauer wrote: > This patch adds a per-process secret to the task struct which > will be used during signal delivery and during a sigreturn. > Also, logic is added in signal.c to generate, place, extract, > clear and verify the signal cookie. > Potentially silly question: it's been a while since I read the SROP paper, but would the technique be effectively mitigated if sigreturn were to zero out the whole signal frame before returning to user mode?