{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-40327","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-04-16T07:20:57.186Z","datePublished":"2025-12-09T04:09:43.522Z","dateUpdated":"2026-05-11T21:47:13.262Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T21:47:13.262Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/core: Fix system hang caused by cpu-clock usage\n\ncpu-clock usage by the async-profiler tool can trigger a system hang,\nwhich got bisected back to the following commit by Octavia Togami:\n\n  18dbcbfabfff (\"perf: Fix the POLL_HUP delivery breakage\") causes this issue\n\nThe root cause of the hang is that cpu-clock is a special type of SW\nevent which relies on hrtimers. The __perf_event_overflow() callback\nis invoked from the hrtimer handler for cpu-clock events, and\n__perf_event_overflow() tries to call cpu_clock_event_stop()\nto stop the event, which calls htimer_cancel() to cancel the hrtimer.\n\nBut that's a recursion into the hrtimer code from a hrtimer handler,\nwhich (unsurprisingly) deadlocks.\n\nTo fix this bug, use hrtimer_try_to_cancel() instead, and set\nthe PERF_HES_STOPPED flag, which causes perf_swevent_hrtimer()\nto stop the event once it sees the PERF_HES_STOPPED flag.\n\n[ mingo: Fixed the comments and improved the changelog. ]"}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/events/core.c"],"versions":[{"version":"18dbcbfabfffc4a5d3ea10290c5ad27f22b0d240","lessThan":"6b8c512811644cf2f5eaf6f44e928683c54127f0","status":"affected","versionType":"git"},{"version":"18dbcbfabfffc4a5d3ea10290c5ad27f22b0d240","lessThan":"eb3182ef0405ff2f6668fd3e5ff9883f60ce8801","status":"affected","versionType":"git"},{"version":"b2de0c9ce8e542b5cb4cd3944620d9dd1ea1f0ac","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/events/core.c"],"versions":[{"version":"6.17","status":"affected"},{"version":"0","lessThan":"6.17","status":"unaffected","versionType":"semver"},{"version":"6.17.8","lessThanOrEqual":"6.17.*","status":"unaffected","versionType":"semver"},{"version":"6.18","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17","versionEndExcluding":"6.17.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17","versionEndExcluding":"6.18"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16.8"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/6b8c512811644cf2f5eaf6f44e928683c54127f0"},{"url":"https://git.kernel.org/stable/c/eb3182ef0405ff2f6668fd3e5ff9883f60ce8801"}],"title":"perf/core: Fix system hang caused by cpu-clock usage","x_generator":{"engine":"bippy-1.2.0"}}}}