CVE-2024-40976

Summary

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

drm/lima: mask irqs in timeout path before hard reset

There is a race condition in which a rendering job might take just long enough to trigger the drm sched job timeout handler but also still complete before the hard reset is done by the timeout handler. This runs into race conditions not expected by the timeout handler. In some very specific cases it currently may result in a refcount imbalance on lima_pm_idle, with a stack dump such as:

[10136.669170] WARNING: CPU: 0 PID: 0 at drivers/gpu/drm/lima/lima_devfreq.c:205 lima_devfreq_record_idle+0xa0/0xb0 … [10136.669459] pc : lima_devfreq_record_idle+0xa0/0xb0 … [10136.669628] Call trace: [10136.669634] lima_devfreq_record_idle+0xa0/0xb0 [10136.669646] lima_sched_pipe_task_done+0x5c/0xb0 [10136.669656] lima_gp_irq_handler+0xa8/0x120 [10136.669666] __handle_irq_event_percpu+0x48/0x160 [10136.669679] handle_irq_event+0x4c/0xc0

We can prevent that race condition entirely by masking the irqs at the beginning of the timeout handler, at which point we give up on waiting for that job entirely. The irqs will be enabled again at the next hard reset which is already done as a recovery by the timeout handler.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxa1d2a6339961efc078208dc3b2f006e9e9a8e119 < 03e7b2f7ae4c0ae5fb8e4e2454ba4008877f196aaffected
LinuxLinuxa1d2a6339961efc078208dc3b2f006e9e9a8e119 < 70aa1f2dec46b6fdb5f6b9f37b6bfa4a4dee0d3aaffected
LinuxLinuxa1d2a6339961efc078208dc3b2f006e9e9a8e119 < 9fd8ddd23793a50dbcd11c6ba51f437f1ea7d344affected
LinuxLinuxa1d2a6339961efc078208dc3b2f006e9e9a8e119 < bdbc4ca77f5eaac15de7230814253cddfed273b1affected
LinuxLinuxa1d2a6339961efc078208dc3b2f006e9e9a8e119 < 58bfd311c93d66d8282bf21ebbf35cc3bb8ad9dbaffected
LinuxLinuxa1d2a6339961efc078208dc3b2f006e9e9a8e119 < a421cc7a6a001b70415aa4f66024fa6178885a14affected
LinuxLinux5.2affected
LinuxLinux0 < 5.2unaffected
LinuxLinux5.10.221 <= 5.10.*unaffected
LinuxLinux5.15.162 <= 5.15.*unaffected
LinuxLinux6.1.96 <= 6.1.*unaffected
LinuxLinux6.6.36 <= 6.6.*unaffected
LinuxLinux6.9.7 <= 6.9.*unaffected
LinuxLinux6.10 <= *unaffected

Weaknesses

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References