CVE-2026-90272

Summary

In the Linux kernel, the following vulnerability has been resolved:

perf: arm_pmuv3: Zero initialize hw_id branch stack field

PERF_SAMPLE_BRANCH_HW_INDEX is supported by BRBE so hw_id is passed to userspace, but it's never set by the BRBE driver. Zero initialize it as it should be according to the docs:

  • For the architectures whose raw branch records are
  • already stored in age order, the hw_idx should be 0.

It's probably too risky to remove PERF_SAMPLE_BRANCH_HW_INDEX from BRBE now in case anyone is setting it and reading the value, but zero initializing the whole struct also protects against the same issue with new fields that are added in the future.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux58074a0fce66c6c97b35ce8a28ed4e7b780f9a8f < 57b72442c1672963fd51ab441ca1b71f6dc79b66affected
LinuxLinux58074a0fce66c6c97b35ce8a28ed4e7b780f9a8f < 988e11b69ef9d4034e19c64407030fa948580c3daffected
LinuxLinux58074a0fce66c6c97b35ce8a28ed4e7b780f9a8f < 7c3b63386c27bed8d59a4b4c283d02860420eb0aaffected
LinuxLinux6.17affected
LinuxLinux0 < 6.17unaffected
LinuxLinux6.18.52 <= 6.18.*unaffected
LinuxLinux7.2.6 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References