[PATCH 4.1 58/86] PCI: Prevent out of bounds access in numa_node override

Greg Kroah-Hartman
2015-11-06T20:06:38Z

From: Sasha Levin <sasha.levin@oracle.com>

commit 1266963170f576d4d08e6310b6963e26d3ff9d1e upstream.

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 <sasha.levin@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/pci/pci-sysfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -216,7 +216,7 @@ static ssize_t numa_node_store(struct de
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);