From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755443AbaBUUdJ (ORCPT ); Fri, 21 Feb 2014 15:33:09 -0500 Received: from terminus.zytor.com ([198.137.202.10]:58569 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755201AbaBUUdH (ORCPT ); Fri, 21 Feb 2014 15:33:07 -0500 Date: Fri, 21 Feb 2014 12:32:26 -0800 From: tip-bot for Vegard Nossum Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, peterz@infradead.org, raistlin@linux.it, vegard.nossum@oracle.com, tglx@linutronix.de, juri.lelli@gmail.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, peterz@infradead.org, raistlin@linux.it, vegard.nossum@oracle.com, tglx@linutronix.de, juri.lelli@gmail.com In-Reply-To: <1392585857-10725-1-git-send-email-vegard.nossum@oracle.com> References: <1392585857-10725-1-git-send-email-vegard.nossum@oracle.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/urgent] sched: Fix information leak in sys_sched_getattr() Git-Commit-ID: 4efbc454ba68def5ef285b26ebfcfdb605b52755 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 4efbc454ba68def5ef285b26ebfcfdb605b52755 Gitweb: http://git.kernel.org/tip/4efbc454ba68def5ef285b26ebfcfdb605b52755 Author: Vegard Nossum AuthorDate: Sun, 16 Feb 2014 22:24:17 +0100 Committer: Thomas Gleixner CommitDate: Fri, 21 Feb 2014 21:27:10 +0100 sched: Fix information leak in sys_sched_getattr() We're copying the on-stack structure to userspace, but forgot to give the right number of bytes to copy. This allows the calling process to obtain up to PAGE_SIZE bytes from the stack (and possibly adjacent kernel memory). This fix copies only as much as we actually have on the stack (attr->size defaults to the size of the struct) and leaves the rest of the userspace-provided buffer untouched. Found using kmemcheck + trinity. Fixes: d50dde5a10f30 ("sched: Add new scheduler syscalls to support an extended scheduling parameters ABI") Cc: Dario Faggioli Cc: Juri Lelli Cc: Ingo Molnar Signed-off-by: Vegard Nossum Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1392585857-10725-1-git-send-email-vegard.nossum@oracle.com Signed-off-by: Thomas Gleixner --- kernel/sched/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 33d030a..a6e7470 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3786,7 +3786,7 @@ static int sched_read_attr(struct sched_attr __user *uattr, attr->size = usize; } - ret = copy_to_user(uattr, attr, usize); + ret = copy_to_user(uattr, attr, attr->size); if (ret) return -EFAULT;