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 acb7121a9316dd146a7cec60af798ecbe42b7681..6d78736563de748c319ade5c0ff5cf210028fc23 100644 (file)
--- 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));