| Sažetak |
In the Linux kernel, the following vulnerability has been resolved:
accel/ivpu: Fix locking order in ivpu_job_submit
Fix deadlock in job submission and abort handling.
When a thread aborts currently executing jobs due to a fault,
it first locks the global lock protecting submitted_jobs (#1).
After the last job is destroyed, it proceeds to release the related context
and locks file_priv (#2). Meanwhile, in the job submission thread,
the file_priv lock (#2) is taken first, and then the submitted_jobs
lock (#1) is obtained when a job is added to the submitted jobs list.
CPU0 CPU1
---- ----
(for example due to a fault) (jobs submissions keep coming)
lock(&vdev->submitted_jobs_lock) #1
ivpu_jobs_abort_all()
job_destroy()
lock(&file_priv->lock) #2
lock(&vdev->submitted_jobs_lock) #1
file_priv_release()
lock(&vdev->context_list_lock)
lock(&file_priv->lock) #2
This order of locking causes a deadlock. To resolve this issue,
change the order of locking in ivpu_job_submit(). |
