{"id":"CVE-2026-99125","title":"s390/pai: Handle multiple PMU stop callback invocations","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/pai: Handle multiple PMU stop callback invocations\n\nHandle the following scenario:\nThe kernel protects itself against a very high sampling load and\nthrottles the s…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 9f66572f2889a5e72a9d7e17787e52f03b1f7bd8 < cf348ec613f75b9774291e47b804fd7010835a6c","Linux >= 9f66572f2889a5e72a9d7e17787e52f03b1f7bd8 < f3110e969ad226ffbb2d9b4bf5387e68d0d9ef40","Linux 6.11"],"published":"2026-10-28","updated":"2026-10-28","sourceUpdated":"2026-10-28T10:34:40.025Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99125","references":[{"url":"https://git.kernel.org/stable/c/cf348ec613f75b9774291e47b804fd7010835a6c"},{"url":"https://git.kernel.org/stable/c/f3110e969ad226ffbb2d9b4bf5387e68d0d9ef40"}],"tags":["cve.org"],"ingestedAt":"2026-10-28T11:09:40.443Z","epss":0.00156,"epssPercentile":0.04773,"slug":"CVE-2026-99125","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ns390/pai: Handle multiple PMU stop callback invocations\n\nHandle the following scenario:\nThe kernel protects itself against a very high sampling load and\nthrottles the sampling using:\n\n  perf_event_throttle() --> PMU->stop()\n\nShortly later the scheduler may terminate the task and removes it from the\nCPU. It again calls\n\n  PMU->stop()\n\nwhich results in two invocations of PMU->stop() called back to back.\nProtect against this and check the PERF_HES_STOPPED bit on function\nentry.  If it is already set return.\nClear bit PERF_HES_STOPPED in PMU->start().\n\nProhibit ioctl(fd, PERF_EVENT_IOC_PERIOD, ...) call for this event.\nIt sets perf_event::event_limit to a positive value and causes\nperf_event_overflow() to invoke pai_stop() call back function when\nperf_event::event_limit hits zero. This is not supported because the\nsample events CRYPTO_ALL and NNPA_ALL are only taken at schedule out\nof a task.\n\nUse list_for_each_entry_safe() for safe iteration over syswide_list\nin pai_have_samples().\n\n## Affected\n\n- `Linux >= 9f66572f2889a5e72a9d7e17787e52f03b1f7bd8 < cf348ec613f75b9774291e47b804fd7010835a6c`\n- `Linux >= 9f66572f2889a5e72a9d7e17787e52f03b1f7bd8 < f3110e969ad226ffbb2d9b4bf5387e68d0d9ef40`\n- `Linux 6.11`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}