diff options
| author | Mauro Carvalho Chehab <mchehab@osg.samsung.com> | 2016-04-28 01:28:26 +0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2016-06-15 23:57:24 +0300 |
| commit | a087ce704b802becbb4b0f2a20f2cb3f6911802e (patch) | |
| tree | 6cfa3f4ac4ef03bc7f7cc5fe4180a956f470213b /drivers/media/usb/uvc/uvc_driver.c | |
| parent | 163f1e93e995048b894c5fc86a6034d16beed740 (diff) | |
| download | linux-a087ce704b802becbb4b0f2a20f2cb3f6911802e.tar.xz | |
[media] media-device: dynamically allocate struct media_devnode
struct media_devnode is currently embedded at struct media_device.
While this works fine during normal usage, it leads to a race
condition during devnode unregister. the problem is that drivers
assume that, after calling media_device_unregister(), the struct
that contains media_device can be freed. This is not true, as it
can't be freed until userspace closes all opened /dev/media devnodes.
In other words, if the media devnode is still open, and media_device
gets freed, any call to an ioctl will make the core to try to access
struct media_device, with will cause an use-after-free and even GPF.
Fix this by dynamically allocating the struct media_devnode and only
freeing it when it is safe.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'drivers/media/usb/uvc/uvc_driver.c')
| -rw-r--r-- | drivers/media/usb/uvc/uvc_driver.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c index 451e84e962e2..302e284a95eb 100644 --- a/drivers/media/usb/uvc/uvc_driver.c +++ b/drivers/media/usb/uvc/uvc_driver.c @@ -1674,7 +1674,7 @@ static void uvc_delete(struct uvc_device *dev) if (dev->vdev.dev) v4l2_device_unregister(&dev->vdev); #ifdef CONFIG_MEDIA_CONTROLLER - if (media_devnode_is_registered(&dev->mdev.devnode)) + if (media_devnode_is_registered(dev->mdev.devnode)) media_device_unregister(&dev->mdev); media_device_cleanup(&dev->mdev); #endif |