Description
In the Linux kernel, the following vulnerability has been resolved:
cpufreq/amd-pstate: handle missing policy in dynamic EPP callbacks
cpufreq_cpu_get() returns NULL when no cpufreq policy is associated with the requested CPU, for example because the CPU is offline or the policy has already been torn down. Both amd_pstate_power_supply_notifier() and amd_pstate_profile_set() acquire a policy via cpufreq_cpu_get() and then pass that pointer to amd_pstate_get_balanced_epp() and amd_pstate_set_epp(), which dereference it unconditionally. A racing CPU hotplug or driver teardown can therefore lead to a NULL pointer dereference on either of these dynamic EPP paths.
The third cpufreq_cpu_get() caller in this file, amd_pstate_verify(), already handles the NULL case. Bring the two new callers in line with that pattern: return NOTIFY_OK from the power-supply notifier (matching the other "nothing to do" exits) and -ENODEV from amd_pstate_profile_set() (the usual cpufreq error for a missing CPU policy).
Found by code inspection; not tested on hardware.
Metrics
No CVSS score has been published yet.
Affected software
Source: the vendor's advisory (CNA). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 471d6659925aa0dcb4ab2520fa5ee3f49dfeab22, < 70c8c8b50d80f681f50ddcc66a9400dd87508913; >= e30ca6dd5345c5b8ba05f346a8e81105352fe571, < f4ade8d224756ab69f108204dde6777bac4664e4; >= e30ca6dd5345c5b8ba05f346a8e81105352fe571, < 39c0cf62fc7851a17782e7efe8dfb2948739c681 |
| Linux | Linux | 7.1 |
References
Timeline
- Published
- Sep 17, 2026
- Last modified
- Oct 19, 2026
- NVD status
- Received