From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751961AbcFEKVb (ORCPT ); Sun, 5 Jun 2016 06:21:31 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:21664 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751874AbcFEKV0 (ORCPT ); Sun, 5 Jun 2016 06:21:26 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Helge Deller , Kees Cook , Greg Kroah-Hartman , Willy Tarreau Subject: [PATCH 3.10 057/143] parisc: Fix kernel crash with reversed copy_from_user() Date: Sun, 5 Jun 2016 12:19:20 +0200 Message-Id: <1465122046-9645-58-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1465122046-9645-1-git-send-email-w@1wt.eu> References: <1465122046-9645-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Signed-off-by: Willy Tarreau --- 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 b3f87a3..0c329b2 100644 --- a/arch/parisc/kernel/traps.c +++ b/arch/parisc/kernel/traps.c @@ -811,6 +811,9 @@ 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); } -- 2.8.0.rc2.1.gbe9624a