From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:55346 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964848AbeFRIVg (ORCPT ); Mon, 18 Jun 2018 04:21:36 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Catalin Marinas , Mark Rutland , Will Deacon , Sasha Levin Subject: [PATCH 4.16 093/279] arm64: ptrace: remove addr_limit manipulation Date: Mon, 18 Jun 2018 10:11:18 +0200 Message-Id: <20180618080612.648341955@linuxfoundation.org> In-Reply-To: <20180618080608.851973560@linuxfoundation.org> References: <20180618080608.851973560@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mark Rutland [ Upstream commit 59275a0c037ed6fabd6354730f1e3104264ab719 ] We transiently switch to KERNEL_DS in compat_ptrace_gethbpregs() and compat_ptrace_sethbpregs(), but in either case this is pointless as we don't perform any uaccess during this window. let's rip out the redundant addr_limit manipulation. Acked-by: Catalin Marinas Signed-off-by: Mark Rutland Cc: Will Deacon Signed-off-by: Will Deacon Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/ptrace.c | 6 ------ 1 file changed, 6 deletions(-) --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -1458,9 +1458,7 @@ static int compat_ptrace_gethbpregs(stru { int ret; u32 kdata; - mm_segment_t old_fs = get_fs(); - set_fs(KERNEL_DS); /* Watchpoint */ if (num < 0) { ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata); @@ -1471,7 +1469,6 @@ static int compat_ptrace_gethbpregs(stru } else { ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata); } - set_fs(old_fs); if (!ret) ret = put_user(kdata, data); @@ -1484,7 +1481,6 @@ static int compat_ptrace_sethbpregs(stru { int ret; u32 kdata = 0; - mm_segment_t old_fs = get_fs(); if (num == 0) return 0; @@ -1493,12 +1489,10 @@ static int compat_ptrace_sethbpregs(stru if (ret) return ret; - set_fs(KERNEL_DS); if (num < 0) ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata); else ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata); - set_fs(old_fs); return ret; }