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=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 AB5BBC6783B for ; Mon, 10 Dec 2018 04:31:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6E12C2082F for ; Mon, 10 Dec 2018 04:31:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6E12C2082F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=altlinux.org 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 S1726825AbeLJEbX (ORCPT ); Sun, 9 Dec 2018 23:31:23 -0500 Received: from vmicros1.altlinux.org ([194.107.17.57]:40572 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726187AbeLJEbW (ORCPT ); Sun, 9 Dec 2018 23:31:22 -0500 Received: from mua.local.altlinux.org (mua.local.altlinux.org [192.168.1.14]) by vmicros1.altlinux.org (Postfix) with ESMTP id 7308672CC71; Mon, 10 Dec 2018 07:31:20 +0300 (MSK) Received: by mua.local.altlinux.org (Postfix, from userid 508) id 623257CEFE9; Mon, 10 Dec 2018 07:31:20 +0300 (MSK) Date: Mon, 10 Dec 2018 07:31:20 +0300 From: "Dmitry V. Levin" To: Michael Ellerman , Oleg Nesterov Cc: Elvira Khabirova , Eugene Syromyatnikov , Benjamin Herrenschmidt , Paul Mackerras , Breno Leitao , Andy Lutomirski , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 23/25] powerpc/ptrace: replace ptrace_report_syscall() with a tracehook call Message-ID: <20181210043120.GW6131@altlinux.org> References: <20181210042352.GA6092@altlinux.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Elvira Khabirova Arch code should use tracehook_*() helpers, as documented in include/linux/tracehook.h, ptrace_report_syscall() is not expected to be used outside that file. The patch does not look very nice, but at least it is correct and opens the way for PTRACE_GET_SYSCALL_INFO API. Co-authored-by: Dmitry V. Levin Fixes: 5521eb4bca2d ("powerpc/ptrace: Add support for PTRACE_SYSEMU") Cc: Michael Ellerman Cc: Oleg Nesterov Cc: Eugene Syromyatnikov Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Breno Leitao Cc: Andy Lutomirski Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Elvira Khabirova Signed-off-by: Dmitry V. Levin --- Notes: v5: reverted to a simple approach, compile- and run-tested v4: rewritten to call tracehook_report_syscall_entry() once, compile-tested v3: add a descriptive comment v2: explicitly ignore tracehook_report_syscall_entry() return code arch/powerpc/kernel/ptrace.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index afb819f4ca68..714c3480c52d 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -3266,12 +3266,17 @@ long do_syscall_trace_enter(struct pt_regs *regs) user_exit(); if (test_thread_flag(TIF_SYSCALL_EMU)) { - ptrace_report_syscall(regs); /* + * A nonzero return code from tracehook_report_syscall_entry() + * tells us to prevent the syscall execution, but we are not + * going to execute it anyway. + * * Returning -1 will skip the syscall execution. We want to * avoid clobbering any register also, thus, not 'gotoing' * skip label. */ + if (tracehook_report_syscall_entry(regs)) + ; return -1; } -- ldv