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.
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.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Thu, 17 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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. | |
| Title | cpufreq/amd-pstate: handle missing policy in dynamic EPP callbacks | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-17T16:10:07.957Z
Reserved: 2026-09-16T12:21:13.871Z
Link: CVE-2026-92492
No data.
Status : Received
Published: 2026-09-17T17:17:51.340
Modified: 2026-09-17T17:17:51.340
Link: CVE-2026-92492
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.