From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758571AbbAGC65 (ORCPT ); Tue, 6 Jan 2015 21:58:57 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:46242 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756928AbbAGBwC (ORCPT ); Tue, 6 Jan 2015 20:52:02 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andy Lutomirski , Linus Torvalds , Steven Rostedt , Ingo Molnar Subject: [PATCH 3.18 39/84] x86/asm/traps: Disable tracing and kprobes in fixup_bad_iret and sync_regs Date: Tue, 6 Jan 2015 17:49:42 -0800 Message-Id: <20150107014030.292260881@linuxfoundation.org> X-Mailer: git-send-email 2.2.1 In-Reply-To: <20150107014029.012974975@linuxfoundation.org> References: <20150107014029.012974975@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Lutomirski 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 Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/traps.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -387,7 +387,7 @@ NOKPROBE_SYMBOL(do_int3); * for scheduling or signal handling. The actual stack switch is done in * entry.S */ -asmlinkage __visible struct pt_regs *sync_regs(struct pt_regs *eregs) +asmlinkage __visible notrace struct pt_regs *sync_regs(struct pt_regs *eregs) { struct pt_regs *regs = eregs; /* Did already sync */ @@ -413,7 +413,7 @@ struct bad_iret_stack { struct pt_regs regs; }; -asmlinkage __visible +asmlinkage __visible notrace struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s) { /* @@ -436,6 +436,7 @@ struct bad_iret_stack *fixup_bad_iret(st BUG_ON(!user_mode_vm(&new_stack->regs)); return new_stack; } +NOKPROBE_SYMBOL(fixup_bad_iret); #endif /*