Withdrawn by the publisher.

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

drm/amd/display: Fix ISM dc_lock deadlock during suspend

[Why] System hang observed during suspend/resume while video is playing. amdgpu_dm_ism_disable() is called under dc_lock and waits for ISM delayed work via disable_delayed_work_sync(). The work handlers themselves take dc_lock, producing an ABBA deadlock when a worker is in flight at suspend time.

[How] Split the disable path into two phases with opposite locking contracts: 1. amdgpu_dm_ism_disable() -- quiesces workers, must NOT hold dc_lock. 2. amdgpu_dm_ism_force_full_power() (new) -- drives the ISM FSM back to FULL_POWER_RUNNING, must hold dc_lock.

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

drm/amd/display: Fix ISM dc_lock deadlock during suspend

[Why] System hang observed during suspend/resume while video is playing. amdgpu_dm_ism_disable() is called under dc_lock and waits for ISM delayed work via disable_delayed_work_sync(). The work handlers themselves take dc_lock, producing an ABBA deadlock when a worker is in flight at suspend time.

[How] Split the disable path into two phases with opposite locking contracts: 1. amdgpu_dm_ism_disable() -- quiesces workers, must NOT hold dc_lock. 2. amdgpu_dm_ism_force_full_power() (new) -- drives the ISM FSM back to FULL_POWER_RUNNING, must hold dc_lock.

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3, Ubuntu:18.04:LTS: linux-gke-4.15, Ubuntu:18.04:LTS: linux-gke-5.4 and 116 more

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix ISM dc_lock deadlock during suspend [Why] System hang observed during suspend/resume while video is playing. amdgpu_dm_ism_disable() is called under dc_lock and waits for ISM delayed work via disable_delayed_work_sync(). The work handlers themselves take dc_lock, producing an ABBA deadlock when a worker is in flight at suspend time. [How] Split the disable path into two phases with opposite locking contracts: 1. amdgpu_dm_ism_disable() -- quiesces workers, must NOT hold dc_lock. 2. amdgpu_dm_ism_force_full_power() (new) -- drives the ISM FSM back to FULL_POWER_RUNNING, must hold dc_lock.

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, darunter möglicherweise die Ausführung von beliebigem Code, die Ausweitung von Berechtigungen, die Offenlegung von Informationen, die Manipulation von Daten oder Denial-of-Service-Zustände.