In the Linux kernel, the following vulnerability has been resolved:

drm/msm/mdp5: Return error code in mdp5_mixer_release when deadlock is detected

There is a possibility for mdp5_get_global_state to return
-EDEADLK when acquiring the modeset lock, but currently global_state in
mdp5_mixer_release doesn't check for if an error is returned.

To avoid a NULL dereference error, let's have mdp5_mixer_release
check if an error is returned and propagate that error.

Patchwork: https://patchwork.freedesktop.org/patch/485181/

https://git.kernel.org/stable/c/09bdeedc1fc53e64b8282e1de67752c69e43bdba

https://git.kernel.org/stable/c/1a5d1474026ea4f1a6f931075ca2adb884af39cf

https://git.kernel.org/stable/c/22d8424913b1348c6324916745fadaeea5273f0e

https://git.kernel.org/stable/c/46e5ce63924a96af452c4fc5ee0bb3b241e1b9f4

https://git.kernel.org/stable/c/47e393061049aff6818d1b9fdca7351411a23fc2

https://git.kernel.org/stable/c/883f1d52a57bf51e1d7a80c432345e2c6222477e

https://git.kernel.org/stable/c/ca75f6f7c6f89365e40f10f641b15981b1f07c31