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=-7.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,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 63852C433EF for ; Mon, 13 Sep 2021 12:59:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 477C360F4A for ; Mon, 13 Sep 2021 12:59:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236424AbhIMNAT (ORCPT ); Mon, 13 Sep 2021 09:00:19 -0400 Received: from pegase2.c-s.fr ([93.17.235.10]:43561 "EHLO pegase2.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229613AbhIMNAS (ORCPT ); Mon, 13 Sep 2021 09:00:18 -0400 Received: from localhost (mailhub3.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4H7RPd63znz9sXR; Mon, 13 Sep 2021 14:59:01 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase2.c-s.fr ([172.26.127.65]) by localhost (pegase2.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id KLpZEGWF4n4X; Mon, 13 Sep 2021 14:59:01 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase2.c-s.fr (Postfix) with ESMTP id 4H7RPc3jNcz9sXP; Mon, 13 Sep 2021 14:59:00 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 69FD78B767; Mon, 13 Sep 2021 14:59:00 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id lqhF7-Io2zmO; Mon, 13 Sep 2021 14:59:00 +0200 (CEST) Received: from PO20335.IDSI0.si.c-s.fr (unknown [172.25.230.107]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 459F88B763; Mon, 13 Sep 2021 14:59:00 +0200 (CEST) Subject: Re: [PATCH v2 3/5] signal: Add unsafe_copy_siginfo_to_user() To: Christoph Hellwig Cc: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Josh Poimboeuf , Peter Zijlstra , Linus Torvalds References: From: Christophe Leroy Message-ID: Date: Mon, 13 Sep 2021 14:59:00 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: fr-FR Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le 02/09/2021 à 08:54, Christoph Hellwig a écrit : > On Mon, Aug 23, 2021 at 03:35:53PM +0000, Christophe Leroy wrote: >> In the same spirit as commit fb05121fd6a2 ("signal: Add >> unsafe_get_compat_sigset()"), implement an 'unsafe' version of >> copy_siginfo_to_user() in order to use it within user access blocks. >> >> For that, also add an 'unsafe' version of clear_user(). > > I'm a little worried about all these unsafe helper in powerpc and the > ever increasing scope of the unsafe sections. Can you at least at > powerpc support to objtool to verify them? objtool verifications has > helped to find quite a few bugs in unsafe sections on x86. Ok, I've started looking at it, I have not found any work at all on objtool for powerpc. I'll see if I can draft something from the ARM64 tentatives. Christophe