2025-04-16 14:12:45
Linux
PUBLISHED
In the Linux kernel, the following vulnerability has been resolved:
powerpc/perf: Fix ref-counting on the PMU vpa_pmu
Commit 176cda0619b6 ("powerpc/perf: Add perf interface to expose vpa
counters") introduced vpa_pmu to expose Book3s-HV nested APIv2 provided
L1<->L2 context switch latency counters to L1 user-space via
perf-events. However the newly introduced PMU named vpa_pmu doesnt
assign ownership of the PMU to the module vpa_pmu. Consequently the
module vpa_pmu can be unloaded while one of the perf-events are still
active, which can lead to kernel oops and panic of the form below on a
Pseries-LPAR:
BUG: Kernel NULL pointer dereference on read at 0x00000058