[PATCH v4 12/12] drm/drm_ioctl.c: Break ioctl when drm device not registered

From: Your Name
Date: Thu Apr 06 2017 - 08:25:40 EST


From: Jeffy Chen <jeffy.chen@xxxxxxxxxxxxxx>

After unbinding drm, the user space may still owns the drm dev fd,
and may still be able to call drm ioctl.

Add a sanity check here to prevent that from happening.

Signed-off-by: Jeffy Chen <jeffy.chen@xxxxxxxxxxxxxx>
Signed-off-by: Your Name <you@xxxxxxxxxxx>
---

Changes in v4: None
Changes in v3: None
Changes in v2: None

drivers/gpu/drm/drm_ioctl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index 7d6deaa..15beb11 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -674,7 +674,7 @@ long drm_ioctl(struct file *filp,

dev = file_priv->minor->dev;

- if (drm_device_is_unplugged(dev))
+ if (drm_device_is_unplugged(dev) || !dev->registered)
return -ENODEV;

is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
--
2.1.4