From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751883AbcFXEXg (ORCPT ); Fri, 24 Jun 2016 00:23:36 -0400 Received: from mail.kernel.org ([198.145.29.136]:43816 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751673AbcFXEXd (ORCPT ); Fri, 24 Jun 2016 00:23:33 -0400 From: Andy Lutomirski To: x86@kernel.org, linux-kernel@vger.kernel.org Cc: linux-arch@vger.kernel.org, Borislav Petkov , Nadav Amit , Kees Cook , Brian Gerst , "kernel-hardening@lists.openwall.com" , Linus Torvalds , Josh Poimboeuf , Jann Horn , Heiko Carstens , Andy Lutomirski Subject: [PATCH v4 12/16] x86/dumpstack: When dumping stack bytes due to OOPS, start with regs->sp Date: Thu, 23 Jun 2016 21:23:07 -0700 Message-Id: <077c8fb1f0a6b7514ef473ed1403b507ff919932.1466741835.git.luto@kernel.org> X-Mailer: git-send-email 2.5.5 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 The comment suggests that show_stack(NULL, NULL) should backtrace the current context, but the code doesn't match the comment. If regs are given, start the "Stack:" hexdump at regs->sp. Signed-off-by: Andy Lutomirski --- arch/x86/kernel/dumpstack_32.c | 4 +++- arch/x86/kernel/dumpstack_64.c | 4 +++- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index fef917e79b9d..948d77da3881 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -96,7 +96,9 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, int i; if (sp == NULL) { - if (task) + if (regs) + sp = (unsigned long *)regs->sp; + else if (task) sp = (unsigned long *)task->thread.sp; else sp = (unsigned long *)&sp; diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index d558a8a49016..a81e1ef73bf2 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -264,7 +264,9 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, * back trace for this cpu: */ if (sp == NULL) { - if (task) + if (regs) + sp = (unsigned long *)regs->sp; + else if (task) sp = (unsigned long *)task->thread.sp; else sp = (unsigned long *)&sp; -- 2.5.5