From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.136]:40195 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754719AbbJGQFC (ORCPT ); Wed, 7 Oct 2015 12:05:02 -0400 Date: Wed, 7 Oct 2015 11:04:58 -0500 From: Bjorn Helgaas To: Sasha Levin Cc: Prarit Bhargava , bhelgaas@google.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI: prevent out of bounds access in numa_node override Message-ID: <20151007160458.GA27633@localhost> References: <1443995369-11399-1-git-send-email-sasha.levin@oracle.com> <20151006193627.GE29420@localhost> <561428CE.2040601@redhat.com> <56152725.10809@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <56152725.10809@oracle.com> Sender: linux-pci-owner@vger.kernel.org List-ID: On Wed, Oct 07, 2015 at 10:07:33AM -0400, Sasha Levin wrote: > > On 10/06/2015 03:36 PM, Bjorn Helgaas wrote: > >> Hi Sasha, > >> > >> On Sun, Oct 04, 2015 at 05:49:29PM -0400, Sasha Levin wrote: > >>> Commit 63692df1 ("PCI: Allow numa_node override via sysfs") didn't check that > >>> the numa node provided by userspace is valid. Passing a node number too high > >>> would attempt to access invalid memory and trigger a kernel panic. > >>> > >>> Fixes: 63692df1 ("PCI: Allow numa_node override via sysfs") > >>> Signed-off-by: Sasha Levin > >>> --- > >>> drivers/pci/pci-sysfs.c | 2 +- > >>> 1 file changed, 1 insertion(+), 1 deletion(-) > >>> > >>> diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c > >>> index 312f23a..e9abca8 100644 > >>> --- a/drivers/pci/pci-sysfs.c > >>> +++ b/drivers/pci/pci-sysfs.c > >>> @@ -216,7 +216,7 @@ static ssize_t numa_node_store(struct device *dev, > >>> if (ret) > >>> return ret; > >>> > >>> - if (!node_online(node)) > >>> + if (node > MAX_NUMNODES || !node_online(node)) > >> > >> This needs to be "node >= MAX_NUMNODES", doesn't it? I'll fix it up if > >> you agree. > > Yup, you're right. OK, applied to for-linus for v4.3 as follows. Thanks a lot, Sasha! commit 0f7b9ad7477f7ce9b30e9ab0048f6e726f11a08a Author: Sasha Levin Date: Sun Oct 4 17:49:29 2015 -0400 PCI: Prevent out of bounds access in numa_node override 63692df103e9 ("PCI: Allow numa_node override via sysfs") didn't check that the numa node provided by userspace is valid. Passing a node number too high would attempt to access invalid memory and trigger a kernel panic. Fixes: 63692df103e9 ("PCI: Allow numa_node override via sysfs") Signed-off-by: Sasha Levin Signed-off-by: Bjorn Helgaas CC: stable@vger.kernel.org # v3.19+ diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 312f23a..9261868 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -216,7 +216,7 @@ static ssize_t numa_node_store(struct device *dev, if (ret) return ret; - if (!node_online(node)) + if (node >= MAX_NUMNODES || !node_online(node)) return -EINVAL; add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);