From: Alexey Kardashevskiy <aik@ozlabs.ru>
Date: Wed, 5 Jun 2013 14:54:16 +0000 (-0600)
Subject: vfio: fix crash on rmmod
X-Git-Tag: v3.10-rc5~12^2
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=9a6aa279d3d17af73a029fa40654e92f4e75e8bb;p=linux-2.6-block.git

vfio: fix crash on rmmod

devtmpfs_delete_node() calls devnode() callback with mode==NULL but
vfio still tries to write there.

The patch fixes this.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---

diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index acb7121a9316..6d78736563de 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1360,7 +1360,7 @@ static const struct file_operations vfio_device_fops = {
  */
 static char *vfio_devnode(struct device *dev, umode_t *mode)
 {
-	if (MINOR(dev->devt) == 0)
+	if (mode && (MINOR(dev->devt) == 0))
 		*mode = S_IRUGO | S_IWUGO;
 
 	return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev));