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=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 B3975C04EB8 for ; Mon, 10 Dec 2018 14:11:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7646820855 for ; Mon, 10 Dec 2018 14:11:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7646820855 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727771AbeLJOLL (ORCPT ); Mon, 10 Dec 2018 09:11:11 -0500 Received: from mx1.redhat.com ([209.132.183.28]:56703 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727197AbeLJOLL (ORCPT ); Mon, 10 Dec 2018 09:11:11 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9529D307D866; Mon, 10 Dec 2018 14:11:10 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.43.17.131]) by smtp.corp.redhat.com (Postfix) with SMTP id 807ED600D6; Mon, 10 Dec 2018 14:11:08 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Mon, 10 Dec 2018 15:11:10 +0100 (CET) Date: Mon, 10 Dec 2018 15:11:07 +0100 From: Oleg Nesterov To: "Dmitry V. Levin" Cc: Andy Lutomirski , Elvira Khabirova , Eugene Syromyatnikov , Kees Cook , Jann Horn , linux-api@vger.kernel.org, strace-devel@lists.strace.io, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 24/25] ptrace: add PTRACE_GET_SYSCALL_INFO request Message-ID: <20181210141107.GB4177@redhat.com> References: <20181210042352.GA6092@altlinux.org> <20181210043126.GX6131@altlinux.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181210043126.GX6131@altlinux.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Mon, 10 Dec 2018 14:11:10 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/10, Dmitry V. Levin wrote: > > +struct ptrace_syscall_info { > + __u8 op; /* PTRACE_SYSCALL_INFO_* */ > + __u8 __pad0[3]; > + __u32 arch; > + __u64 instruction_pointer; > + __u64 stack_pointer; > + __u64 frame_pointer; > + union { > + struct { > + __u64 nr; > + __u64 args[6]; > + } entry; > + struct { > + __s64 rval; > + __u8 is_error; > + __u8 __pad1[7]; > + } exit; > + struct { > + __u64 nr; > + __u64 args[6]; > + __u32 ret_data; > + __u8 __pad2[4]; > + } seccomp; > + }; > +}; Could you explain why ptrace_syscall_info needs __pad{0,1,2} ? I simply can't understand why... Otherwise the patch looks good to me. I am not going to discuss the API and data layout, I am fine with anything which suits user-space needs. I think the patch is technically correct, feel free to add Reviewed-by: Oleg Nesterov