[3.19.y-ckt stable] Patch "PCI: Prevent out of bounds access in numa_node override" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    PCI: Prevent out of bounds access in numa_node override

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt12.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 5843b719b2d9fdcfaf6cccd56042cbdcba6c659a Mon Sep 17 00:00:00 2001
From: Mathias Krause <minipli at googlemail.com>
Date: Mon, 9 Nov 2015 20:00:27 +0100
Subject: PCI: Prevent out of bounds access in numa_node override

commit 3dcc8d39cf15fa3ceabedcffcbd3958fe953555a upstream.

Commit 1266963170f5 ("PCI: Prevent out of bounds access in numa_node
override") missed that the user-provided node could also be negative.
Handle this case as well to avoid out-of-bounds accesses to the
node_states[] array.  However, allow the special value -1, i.e.
NUMA_NO_NODE, to be able to set the 'no specific node' configuration.

Fixes: 1266963170f5 ("PCI: Prevent out of bounds access in numa_node override")
Fixes: 63692df103e9 ("PCI: Allow numa_node override via sysfs")
Signed-off-by: Mathias Krause <minipli at googlemail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas at google.com>
CC: Sasha Levin <sasha.levin at oracle.com>
CC: Prarit Bhargava <prarit at redhat.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/pci/pci-sysfs.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 9261868..eead54c 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -216,7 +216,10 @@ static ssize_t numa_node_store(struct device *dev,
 	if (ret)
 		return ret;

-	if (node >= MAX_NUMNODES || !node_online(node))
+	if ((node < 0 && node != NUMA_NO_NODE) || node >= MAX_NUMNODES)
+		return -EINVAL;
+
+	if (node != NUMA_NO_NODE && !node_online(node))
 		return -EINVAL;

 	add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
--
1.9.1