Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753014AbcDVLRr (ORCPT ); Fri, 22 Apr 2016 07:17:47 -0400 Received: from mx2.suse.de ([195.135.220.15]:43971 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753544AbcDVLGV (ORCPT ); Fri, 22 Apr 2016 07:06:21 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Helge Deller , Kees Cook , Jiri Slaby Subject: [PATCH 3.12 41/78] parisc: Fix kernel crash with reversed copy_from_user() Date: Fri, 22 Apr 2016 13:05:24 +0200 Message-Id: <168d26de82bf018acec1768ddf1f818e434d00be.1461323133.git.jslaby@suse.cz> X-Mailer: git-send-email 2.8.1 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 Content-Length: 1221 Lines: 38 From: Helge Deller 3.12-stable review patch. If anyone has any objections, please let me know. =============== 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: Jiri Slaby --- arch/parisc/kernel/traps.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/parisc/kernel/traps.c b/arch/parisc/kernel/traps.c index 1cd1d0c83b6d..cf87b94be7f3 100644 --- a/arch/parisc/kernel/traps.c +++ b/arch/parisc/kernel/traps.c @@ -806,6 +806,9 @@ void notrace handle_interruption(int code, struct pt_regs *regs) if (fault_space == 0 && !in_atomic()) { + /* 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); } -- 2.8.1