From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752490Ab1GHAD5 (ORCPT ); Thu, 7 Jul 2011 20:03:57 -0400 Received: from mx1.vsecurity.com ([209.67.252.12]:51396 "EHLO mx1.vsecurity.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750932Ab1GHAD4 (ORCPT ); Thu, 7 Jul 2011 20:03:56 -0400 Subject: [PATCH] xtensa: prevent arbitrary read in ptrace From: Dan Rosenberg To: chris@zankel.net Cc: linux-kernel@vger.kernel.org, security@kernel.org Content-Type: text/plain; charset="UTF-8" Date: Thu, 07 Jul 2011 20:03:54 -0400 Message-ID: <1310083434.2139.4.camel@anubis> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Prevent an arbitrary kernel read. Check the user pointer with access_ok() before copying data in. Signed-off-by: Dan Rosenberg Cc: stable@kernel.org --- arch/xtensa/kernel/ptrace.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c index c72c947..ddce75e 100644 --- a/arch/xtensa/kernel/ptrace.c +++ b/arch/xtensa/kernel/ptrace.c @@ -147,6 +147,9 @@ int ptrace_setxregs(struct task_struct *child, void __user *uregs) elf_xtregs_t *xtregs = uregs; int ret = 0; + if (!access_ok(VERIFY_READ, uregs, sizeof(elf_xtregs_t))) + return -EIO; + #if XTENSA_HAVE_COPROCESSORS /* Flush all coprocessors before we overwrite them. */ coprocessor_flush_all(ti);