{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-37878","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-04-16T04:51:23.960Z","datePublished":"2025-05-09T06:45:42.459Z","dateUpdated":"2026-05-11T21:16:51.715Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T21:16:51.715Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/core: Fix WARN_ON(!ctx) in __free_event() for partial init\n\nMove the get_ctx(child_ctx) call and the child_event->ctx assignment to\noccur immediately after the child event is allocated. Ensure that\nchild_event->ctx is non-NULL before any subsequent error path within\ninherit_event calls free_event(), satisfying the assumptions of the\ncleanup code.\n\nDetails:\n\nThere's no clear Fixes tag, because this bug is a side-effect of\nmultiple interacting commits over time (up to 15 years old), not\na single regression.\n\nThe code initially incremented refcount then assigned context\nimmediately after the child_event was created. Later, an early\nvalidity check for child_event was added before the\nrefcount/assignment. Even later, a WARN_ON_ONCE() cleanup check was\nadded, assuming event->ctx is valid if the pmu_ctx is valid.\nThe problem is that the WARN_ON_ONCE() could trigger after the initial\ncheck passed but before child_event->ctx was assigned, violating its\nprecondition. The solution is to assign child_event->ctx right after\nits initial validation. This ensures the context exists for any\nsubsequent checks or cleanup routines, resolving the WARN_ON_ONCE().\n\nTo resolve it, defer the refcount update and child_event->ctx assignment\ndirectly after child_event->pmu_ctx is set but before checking if the\nparent event is orphaned. The cleanup routine depends on\nevent->pmu_ctx being non-NULL before it verifies event->ctx is\nnon-NULL. This also maintains the author's original intent of passing\nin child_ctx to find_get_pmu_context before its refcount/assignment.\n\n[ mingo: Expanded the changelog from another email by Gabriel Shahrouzi. ]"}],"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":"7ef5aa081f989ecfecc1df02068a80aebbd3ec31","lessThan":"90dc6c1e3b200812da8d0aa030e1b7fda8226d0e","status":"affected","versionType":"git"},{"version":"1209b0b29fd472e7dbd2b06544b019dd9f9b7e51","lessThan":"cb56cd11feabf99e08bc18960700a53322ffcea7","status":"affected","versionType":"git"},{"version":"c70ca298036c58a88686ff388d3d367e9d21acf0","lessThan":"0ba3a4ab76fd3367b9cb680cad70182c896c795c","status":"affected","versionType":"git"},{"version":"315a50c6b1c6ce191f19f3372935d8e2ed9b53a6","status":"affected","versionType":"git"}]},{"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":"6.12.24","lessThan":"6.12.26","status":"affected","versionType":"semver"},{"version":"6.14.3","lessThan":"6.14.5","status":"affected","versionType":"semver"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.24","versionEndExcluding":"6.12.26"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14.3","versionEndExcluding":"6.14.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13.12"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/90dc6c1e3b200812da8d0aa030e1b7fda8226d0e"},{"url":"https://git.kernel.org/stable/c/cb56cd11feabf99e08bc18960700a53322ffcea7"},{"url":"https://git.kernel.org/stable/c/0ba3a4ab76fd3367b9cb680cad70182c896c795c"}],"title":"perf/core: Fix WARN_ON(!ctx) in __free_event() for partial init","x_generator":{"engine":"bippy-1.2.0"}}}}