perf/x86/intel: Prevent drain_pebs() reentry
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.4, 6.6.160, 6.12.114, 6.18.53, 7.2.7
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: perf/x86/intel: Prevent drain_pebs() reentry The PEBS buffer is shared by all events on a CPU, so drain_pebs() must not be reentered. If so, one instance may observe stale buffer state and potentially access out-of-bound memory. Most invocations happen in NMI context, which naturally prevents reentry. However, drain_pebs() is also reachable from process context via intel_pmu_drain_pebs_buffer(). In those paths, the PMU is often already disabled, but not guaranteed. For example, __intel_pmu_pebs_disable() only disables the target counter, so other active counters can still raise a PMI and interrupt an in-flight drain_pebs(). Here is an example, __perf_addr_filters_adjust() perf_event_stop() __perf_event_stop() x86_pmu_stop() (event->pmu->stop) intel_pmu_disable_event() intel_pmu_pebs_disable() __intel_pmu_pebs_disable() intel_pmu_drain_large_pebs() intel_pmu_drain_pebs_buffer() Introduce __intel_pmu_quiesce() and __intel_pmu_resume() helpers and use them in intel_pmu_drain_large_pebs() to disable the full PMU around the intel_pmu_drain_pebs_buffer() call, preventing reentry. Also add a warning in intel_pmu_drain_pebs_buffer() when the full PMU is not disabled.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From b752ea0c28e3f7f0aaaad6abf84f735eebc37a60 · fixed in 9882068ed242fcd4743f53027e8c790e88dcafff; From b752ea0c28e3f7f0aaaad6abf84f735eebc37a60 · fixed in 999e482fdf89400cc1ae937680fc05096b4c915b; From b752ea0c28e3f7f0aaaad6abf84f735eebc37a60 · fixed in a5fe19dd8b3ed5fad6e5e0f0c58c7245043ee4af; From b752ea0c28e3f7f0aaaad6abf84f735eebc37a60 · fixed in c55599c0ec2aa020e41a0599c3044c56d8a2e7d9; From b752ea0c28e3f7f0aaaad6abf84f735eebc37a60 · fixed in a56c03a397e2cd0c4cf8da96dcd6214f7d0e7d8c; From 6.3.7 · fixed in 6.4
- Linux Linux
6.4
- KernelLinux
From 6.4.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.114; From 6.13.0 · fixed in 6.18.53; From 6.19.0 · fixed in 7.2.7