CVE-2026-98937

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

perf/core: Check kernel access when kernel callchains are requested

perf event open() currently gates perf allow kernel() only on !attr.exclude kernel.

However, users can still request kernel callchain collection with attr.exclude callchain kernel == 0 even when attr.exclude kernel == 1. That still requires kernel profiling privilege, but the existing check does not enforce it.

Update the permission check to call perf allow kernel() when either kernel sampling is requested or kernel callchains are requested.

This keeps permission checks aligned with requested data and prevents unprivileged use of kernel callchain capture.