Bug 2334686 (CVE-2024-56683)

Summary: CVE-2024-56683 kernel: drm/vc4: hdmi: Avoid hang with debug registers when suspended
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
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Hardware: All   
OS: Linux   
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Description OSIDB Bzimport 2024-12-28 10:02:35 UTC 
In the Linux kernel, the following vulnerability has been resolved:

drm/vc4: hdmi: Avoid hang with debug registers when suspended

Trying to read /sys/kernel/debug/dri/1/hdmi1_regs
when the hdmi is disconnected results in a fatal system hang.

This is due to the pm suspend code disabling the dvp clock.
That is just a gate of the 108MHz clock in DVP_HT_RPI_MISC_CONFIG,
which results in accesses hanging AXI bus.

Protect against this.
Comment 1 Avinash Hanwate 2024-12-29 06:12:13 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024122833-CVE-2024-56683-14c3@gregkh/T