| ID |
CVE-2025-68375
|
| Sažetak |
In the Linux kernel, the following vulnerability has been resolved:
perf/x86: Fix NULL event access and potential PEBS record loss
When intel_pmu_drain_pebs_icl() is called to drain PEBS records, the
perf_event_overflow() could be called to process the last PEBS record.
While perf_event_overflow() could trigger the interrupt throttle and
stop all events of the group, like what the below call-chain shows.
perf_event_overflow()
-> __perf_event_overflow()
->__perf_event_account_interrupt()
-> perf_event_throttle_group()
-> perf_event_throttle()
-> event->pmu->stop()
-> x86_pmu_stop()
The side effect of stopping the events is that all corresponding event
pointers in cpuc->events[] array are cleared to NULL.
Assume there are two PEBS events (event a and event b) in a group. When
intel_pmu_drain_pebs_icl() calls perf_event_overflow() to process the
last PEBS record of PEBS event a, interrupt throttle is triggered and
all pointers of event a and event b are cleared to NULL. Then
intel_pmu_drain_pebs_icl() tries to process the last PEBS record of
event b and encounters NULL pointer access.
To avoid this issue, move cpuc->events[] clearing from x86_pmu_stop()
to x86_pmu_del(). It's safe since cpuc->active_mask or
cpuc->pebs_enabled is always checked before access the event pointer
from cpuc->events[]. |
| Reference |
|
| CVSS |
| Base: | 0.0 |
| Impact: | None |
| Exploitability: | None |
|
| Pristup |
| Vektor | Složenost | Autentikacija |
| None |
None |
None |
|
| Impact |
| Povjerljivost | Cjelovitost | Dostupnost |
| None |
None |
None |
|
| CVSS vektor |
None |
| Zadnje važnije ažuriranje |
24-12-2025 - 11:16 |
| Objavljeno |
24-12-2025 - 11:16 |
