From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756542AbbA2JAn (ORCPT ); Thu, 29 Jan 2015 04:00:43 -0500 Received: from ip4-83-240-67-251.cust.nbox.cz ([83.240.67.251]:44737 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752597AbbA2JAk (ORCPT ); Thu, 29 Jan 2015 04:00:40 -0500 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Andy Lutomirski , Linus Torvalds , Steven Rostedt , Ingo Molnar , Ben Hutchings , Jiri Slaby Subject: [PATCH 3.12 162/176] x86/asm/traps: Disable tracing and kprobes in fixup_bad_iret and sync_regs Date: Wed, 28 Jan 2015 15:29:52 +0100 Message-Id: X-Mailer: git-send-email 2.2.2 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andy Lutomirski 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 7ddc6a2199f1da405a2fb68c40db8899b1a8cd87 upstream. These functions can be executed on the int3 stack, so kprobes are dangerous. Tracing is probably a bad idea, too. Fixes: b645af2d5905 ("x86_64, traps: Rework bad_iret") Signed-off-by: Andy Lutomirski Cc: Linus Torvalds Cc: Steven Rostedt Link: http://lkml.kernel.org/r/50e33d26adca60816f3ba968875801652507d0c4.1416870125.git.luto@amacapital.net Signed-off-by: Ingo Molnar [bwh: Backported to 3.10: - Use __kprobes instead of NOKPROBE_SYMBOL() - Adjust context] Signed-off-by: Ben Hutchings Signed-off-by: Jiri Slaby --- arch/x86/kernel/traps.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 5739ab5359a3..88f3d3b86802 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -369,7 +369,7 @@ exit: * for scheduling or signal handling. The actual stack switch is done in * entry.S */ -asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) +asmlinkage notrace __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) { struct pt_regs *regs = eregs; /* Did already sync */ @@ -394,7 +394,7 @@ struct bad_iret_stack { struct pt_regs regs; }; -asmlinkage __visible +asmlinkage __visible notrace __kprobes struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s) { /* -- 2.2.2