From patchwork Wed Jul 22 23:13:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Karcher X-Patchwork-Id: 11679299 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F128113A4 for ; Wed, 22 Jul 2020 23:21:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE2FE2086A for ; Wed, 22 Jul 2020 23:21:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733201AbgGVXVK (ORCPT ); Wed, 22 Jul 2020 19:21:10 -0400 Received: from outpost17.zedat.fu-berlin.de ([130.133.4.110]:40571 "EHLO outpost17.zedat.fu-berlin.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733132AbgGVXVK (ORCPT ); Wed, 22 Jul 2020 19:21:10 -0400 X-Greylist: delayed 420 seconds by postgrey-1.27 at vger.kernel.org; Wed, 22 Jul 2020 19:21:08 EDT Received: from relay1.zedat.fu-berlin.de ([130.133.4.67]) by outpost.zedat.fu-berlin.de (Exim 4.93) with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (envelope-from ) id 1jyNwD-000bZx-OI; Thu, 23 Jul 2020 01:14:13 +0200 Received: from mx.physik.fu-berlin.de ([160.45.64.218]) by relay1.zedat.fu-berlin.de (Exim 4.93) with esmtps (TLS1.2) tls TLS_DHE_RSA_WITH_AES_128_CBC_SHA (envelope-from ) id 1jyNwD-001IvP-Lp; Thu, 23 Jul 2020 01:14:13 +0200 Received: from epyc.physik.fu-berlin.de ([160.45.64.180]) by mx.physik.fu-berlin.de with esmtps (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1jyNw6-0002TM-Ay; Thu, 23 Jul 2020 01:14:06 +0200 Received: from mkarcher by epyc.physik.fu-berlin.de with local (Exim 4.94 #2 (Debian)) id 1jyNw6-001lBg-23; Thu, 23 Jul 2020 01:14:06 +0200 From: Michael Karcher To: linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Yoshinori Sato , Rich Felker , Adrian Glaubitz , Michael Karcher Subject: [PATCH 2/4] sh: Rearrange blocks in entry-common.S Date: Thu, 23 Jul 2020 01:13:20 +0200 Message-Id: <20200722231322.419642-2-kernel@mkarcher.dialup.fu-berlin.de> X-Mailer: git-send-email 2.28.0.rc1 In-Reply-To: <20200722231322.419642-1-kernel@mkarcher.dialup.fu-berlin.de> References: <20200722231322.419642-1-kernel@mkarcher.dialup.fu-berlin.de> MIME-Version: 1.0 X-Originating-IP: 160.45.64.218 X-ZEDAT-Hint: RV Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org This avoids out-of-range jumps that get auto-replaced by the assembler and prepares for the changes needed to implement SECCOMP_FILTER cleanly. Signed-off-by: Michael Karcher --- arch/sh/kernel/entry-common.S | 57 ++++++++++++++++++----------------- 1 file changed, 29 insertions(+), 28 deletions(-) diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S index 9bac5bbb67f3..c4d88d61890d 100644 --- a/arch/sh/kernel/entry-common.S +++ b/arch/sh/kernel/entry-common.S @@ -178,34 +178,6 @@ syscall_exit_work: bra resume_userspace nop - .align 2 -syscall_trace_entry: - ! Yes it is traced. - mov r15, r4 - mov.l 7f, r11 ! Call do_syscall_trace_enter which notifies - jsr @r11 ! superior (will chomp R[0-7]) - nop - mov.l r0, @(OFF_R0,r15) ! Save return value - ! Reload R0-R4 from kernel stack, where the - ! parent may have modified them using - ! ptrace(POKEUSR). (Note that R0-R2 are - ! reloaded from the kernel stack by syscall_call - ! below, so don't need to be reloaded here.) - ! This allows the parent to rewrite system calls - ! and args on the fly. - mov.l @(OFF_R4,r15), r4 ! arg0 - mov.l @(OFF_R5,r15), r5 - mov.l @(OFF_R6,r15), r6 - mov.l @(OFF_R7,r15), r7 ! arg3 - mov.l @(OFF_R3,r15), r3 ! syscall_nr - ! - mov.l 6f, r10 ! Number of syscalls - cmp/hs r10, r3 - bf syscall_call - mov #-ENOSYS, r0 - bra syscall_exit - mov.l r0, @(OFF_R0,r15) ! Return value - __restore_all: mov #OFF_SR, r0 mov.l @(r0,r15), r0 ! get status register @@ -388,6 +360,35 @@ syscall_exit: bf syscall_exit_work bra __restore_all nop + + .align 2 +syscall_trace_entry: + ! Yes it is traced. + mov r15, r4 + mov.l 7f, r11 ! Call do_syscall_trace_enter which notifies + jsr @r11 ! superior (will chomp R[0-7]) + nop + mov.l r0, @(OFF_R0,r15) ! Save return value + ! Reload R0-R4 from kernel stack, where the + ! parent may have modified them using + ! ptrace(POKEUSR). (Note that R0-R2 are + ! reloaded from the kernel stack by syscall_call + ! below, so don't need to be reloaded here.) + ! This allows the parent to rewrite system calls + ! and args on the fly. + mov.l @(OFF_R4,r15), r4 ! arg0 + mov.l @(OFF_R5,r15), r5 + mov.l @(OFF_R6,r15), r6 + mov.l @(OFF_R7,r15), r7 ! arg3 + mov.l @(OFF_R3,r15), r3 ! syscall_nr + ! + mov.l 6f, r10 ! Number of syscalls + cmp/hs r10, r3 + bf syscall_call + mov #-ENOSYS, r0 + bra syscall_exit + mov.l r0, @(OFF_R0,r15) ! Return value + .align 2 #if !defined(CONFIG_CPU_SH2) 1: .long TRA