drm/vc4: drain the hangcheck timer and works on V3D unbind
Impact
In the Linux kernel, the following vulnerability has been resolved:
Source excerpt · LinuxAffected packages
Affected products
Vendor version evidence. Product records are separate from automatic dependency matching.
Linux · Linux
Other versions: unaffected
| Version / range | Source status |
|---|---|
| d5b1a78a772f1e31a94f8babfa964152ec5e9aa5 to before 17c5fa371de2d5508755cd4cd227cc8e2bb99240 | affected |
| d5b1a78a772f1e31a94f8babfa964152ec5e9aa5 to before a046cd60ff3f4a8c8e672b3b18902682c1f91731 | affected |
| d5b1a78a772f1e31a94f8babfa964152ec5e9aa5 to before e61465d3e0292daebf4dbb34e0add635e2439569 | affected |
| d5b1a78a772f1e31a94f8babfa964152ec5e9aa5 to before ade226dfd28cf2fd1dce143c556d1ee77d953696 | affected |
| d5b1a78a772f1e31a94f8babfa964152ec5e9aa5 to before 94cf5971b1d04c6382437387c4dc3836cc7a1437 | affected |
Linux · Linux
Other versions: affected
| Version / range | Source status |
|---|---|
| 4.5 | affected |
| 0 to before 4.5 | unaffected |
| 6.6.160 through 6.6.* (inclusive) | unaffected |
| 6.12.113 through 6.12.* (inclusive) | unaffected |
| 6.18.57 through 6.18.* (inclusive) | unaffected |
| 7.2.11 through 7.2.* (inclusive) | unaffected |
| 7.3 through * (inclusive) | unaffected |
Original source description
In the Linux kernel, the following vulnerability has been resolved:
drm/vc4: drain the hangcheck timer and works on V3D unbind
Nothing stops the hangcheck timer that submitted jobs arm, or the job_done_work that the render-done interrupt queues, at teardown: vc4_irq_disable() cancels only overflow_mem_work, and vc4_gem_destroy() runs from the drm-managed release, after vc4_v3d_unbind() has already uninstalled the V3D interrupt and cleared vc4->v3d. A timer still armed by then reads V3D registers through the NULL vc4->v3d pointer, and the late callbacks run on the vc4_dev embedding them after it has been freed.
Drain them in vc4_v3d_unbind(): shut the timer down and cancel reset_work before the interrupt is taken down, because its vc4_irq_reset() re-enables it, then flush job_done_work so that completions queued at teardown still release their jobs.
This issue was found by an in-house static analysis tool.
References
- Source reference git.kernel.org/stable/c/17c5fa371de2d5508755cd4cd227cc8e2bb99240
- Source reference git.kernel.org/stable/c/a046cd60ff3f4a8c8e672b3b18902682c1f91731
- Source reference git.kernel.org/stable/c/e61465d3e0292daebf4dbb34e0add635e2439569
- Source reference git.kernel.org/stable/c/ade226dfd28cf2fd1dce143c556d1ee77d953696
- Source reference git.kernel.org/stable/c/94cf5971b1d04c6382437387c4dc3836cc7a1437