Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752853AbcDRCa4 (ORCPT ); Sun, 17 Apr 2016 22:30:56 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:35728 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752452AbcDRCax (ORCPT ); Sun, 17 Apr 2016 22:30:53 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Helge Deller , Kees Cook Subject: [PATCH 4.5 006/124] parisc: Fix kernel crash with reversed copy_from_user() Date: Mon, 18 Apr 2016 11:27:58 +0900 Message-Id: <20160418022616.080911218@linuxfoundation.org> X-Mailer: git-send-email 2.8.0 In-Reply-To: <20160418022615.726954227@linuxfoundation.org> References: <20160418022615.726954227@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1117 Lines: 36 4.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Helge Deller commit ef72f3110d8b19f4c098a0bff7ed7d11945e70c6 upstream. The kernel module testcase (lib/test_user_copy.c) exhibited a kernel crash on parisc if the parameters for copy_from_user were reversed ("illegal reversed copy_to_user" testcase). Fix this potential crash by checking the fault handler if the faulting address is in the exception table. Signed-off-by: Helge Deller Cc: Kees Cook Signed-off-by: Greg Kroah-Hartman --- arch/parisc/kernel/traps.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/parisc/kernel/traps.c +++ b/arch/parisc/kernel/traps.c @@ -798,6 +798,9 @@ void notrace handle_interruption(int cod if (fault_space == 0 && !faulthandler_disabled()) { + /* Clean up and return if in exception table. */ + if (fixup_exception(regs)) + return; pdc_chassis_send_status(PDC_CHASSIS_DIRECT_PANIC); parisc_terminate("Kernel Fault", regs, code, fault_address); }