Affected: Linux

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

drm/msm: don't tear down KMS twice when KMS init fails

When priv->kms_init() (mdp4_kms_init() / mdp5_kms_init()) fails partway through, both display drivers already tear their KMS state down via mdp4_destroy() / mdp5_kms_destroy() before returning the error. The common error path in msm_drm_init() then runs msm_drm_uninit() -> msm_drm_kms_uninit(), which tries to destroy the very same KMS a second time, which causes a use-after-free crash.

Bring MDP4/MDP5 in line with the DPU driver whose dpu_kms_init() doesn't perform error cleanup on the failure. Let the common path own the cleanup, instead of freeing the KMS from their error paths.

The crash trace for the reference:

__lock_acquire from lock_acquire (kernel/locking/lockdep.c:5906 kernel/locking/lockdep.c:5863) lock_acquire from touch_wq_lockdep_map (kernel/workqueue.c:4094 (discriminator 1)) touch_wq_lockdep_map from __flush_workqueue (kernel/workqueue.c:4136) __flush_workqueue from msm_drm_kms_uninit (drivers/gpu/drm/msm/msm_kms.c:243 (discriminator 33)) msm_drm_kms_uninit from msm_drm_uninit (drivers/gpu/drm/msm/msm_drv.c:93) msm_drm_uninit from msm_drm_init (drivers/gpu/drm/msm/msm_drv.c:184) msm_drm_init from try_to_bring_up_aggregate_device (drivers/base/component.c:249 drivers/base/component.c:227) try_to_bring_up_aggregate_device from __component_add (drivers/base/component.c:269 drivers/base/component.c:748) __component_add f…