From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752909AbdHJM25 (ORCPT ); Thu, 10 Aug 2017 08:28:57 -0400 Received: from terminus.zytor.com ([65.50.211.136]:33479 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752800AbdHJM2y (ORCPT ); Thu, 10 Aug 2017 08:28:54 -0400 Date: Thu, 10 Aug 2017 05:23:09 -0700 From: tip-bot for Andy Lutomirski Message-ID: Cc: peterz@infradead.org, bp@alien8.de, tglx@linutronix.de, mingo@kernel.org, rostedt@goodmis.org, linux-kernel@vger.kernel.org, dvlasenk@redhat.com, jpoimboe@redhat.com, hpa@zytor.com, brgerst@gmail.com, luto@kernel.org, torvalds@linux-foundation.org Reply-To: tglx@linutronix.de, mingo@kernel.org, bp@alien8.de, peterz@infradead.org, rostedt@goodmis.org, brgerst@gmail.com, hpa@zytor.com, dvlasenk@redhat.com, jpoimboe@redhat.com, linux-kernel@vger.kernel.org, luto@kernel.org, torvalds@linux-foundation.org In-Reply-To: <0b76f6dbe477b7b1a81938fddcc3c483d48f0ff2.1502314765.git.luto@kernel.org> References: <0b76f6dbe477b7b1a81938fddcc3c483d48f0ff2.1502314765.git.luto@kernel.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/asm] x86/asm/32: Fix regs_get_register() on segment registers Git-Commit-ID: 603e492e861861ddfec7139a007abad74f0d3af0 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 603e492e861861ddfec7139a007abad74f0d3af0 Gitweb: http://git.kernel.org/tip/603e492e861861ddfec7139a007abad74f0d3af0 Author: Andy Lutomirski AuthorDate: Wed, 9 Aug 2017 14:39:45 -0700 Committer: Ingo Molnar CommitDate: Thu, 10 Aug 2017 13:14:58 +0200 x86/asm/32: Fix regs_get_register() on segment registers The segment register high words on x86_32 may contain garbage. Teach regs_get_register() to read them as u16 instead of unsigned long. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/0b76f6dbe477b7b1a81938fddcc3c483d48f0ff2.1502314765.git.luto@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/include/asm/ptrace.h | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index a29f828..91c04c8 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -196,6 +196,17 @@ static inline unsigned long regs_get_register(struct pt_regs *regs, if (offset == offsetof(struct pt_regs, sp) && regs->cs == __KERNEL_CS) return kernel_stack_pointer(regs); + + /* The selector fields are 16-bit. */ + if (offset == offsetof(struct pt_regs, cs) || + offset == offsetof(struct pt_regs, ss) || + offset == offsetof(struct pt_regs, ds) || + offset == offsetof(struct pt_regs, es) || + offset == offsetof(struct pt_regs, fs) || + offset == offsetof(struct pt_regs, gs)) { + return *(u16 *)((unsigned long)regs + offset); + + } #endif return *(unsigned long *)((unsigned long)regs + offset); }