{"id":"CVE-2025-39859","title":"ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog\n\nThe ptp_ocp_detach() only shuts down the watchdog timer if it is\npending. However, if the timer handler i…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"adp","vendor":"Linux","product":"Linux","affected":["Linux >= 773bda96492153e11d21eb63ac814669b51fc701 < e2a6eabe5304a789b7d40ce2576cd80154255e51","Linux >= 773bda96492153e11d21eb63ac814669b51fc701 < aad70bdfc8244616e48c434310cab241a3f17781","Linux >= 773bda96492153e11d21eb63ac814669b51fc701 < f10d3c7267ac7387a5129d5506c3c5f2460cfd9b","Linux >= 773bda96492153e11d21eb63ac814669b51fc701 < 8bf935cf789872350b04c1a6468b0a509f67afb2","Linux 5.15"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-01-14T19:22:59.022358Z"},"published":"2025-09-19","updated":"2026-10-21","sourceUpdated":"2026-10-21T12:37:29.513Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-39859","references":[{"url":"https://git.kernel.org/stable/c/e2a6eabe5304a789b7d40ce2576cd80154255e51"},{"url":"https://git.kernel.org/stable/c/aad70bdfc8244616e48c434310cab241a3f17781"},{"url":"https://git.kernel.org/stable/c/f10d3c7267ac7387a5129d5506c3c5f2460cfd9b"},{"url":"https://git.kernel.org/stable/c/8bf935cf789872350b04c1a6468b0a509f67afb2"}],"tags":["cve.org"],"epss":0.00195,"epssPercentile":0.09087,"ingestedAt":"2026-10-21T12:48:53.687Z","slug":"CVE-2025-39859","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog\n\nThe ptp_ocp_detach() only shuts down the watchdog timer if it is\npending. However, if the timer handler is already running, the\ntimer_delete_sync() is not called. This leads to race conditions\nwhere the devlink that contains the ptp_ocp is deallocated while\nthe timer handler is still accessing it, resulting in use-after-free\nbugs. The following details one of the race scenarios.\n\n(thread 1)                           | (thread 2)\nptp_ocp_remove()                     |\n  ptp_ocp_detach()                   | ptp_ocp_watchdog()\n    if (timer_pending(&bp->watchdog))|   bp = timer_container_of()\n      timer_delete_sync()            |\n                                     |\n  devlink_free(devlink) //free       |\n                                     |   bp-> //use\n\nResolve this by unconditionally calling timer_delete_sync() to ensure\nthe timer is reliably deactivated, preventing any access after free.\n\n## Affected\n\n- `Linux >= 773bda96492153e11d21eb63ac814669b51fc701 < e2a6eabe5304a789b7d40ce2576cd80154255e51`\n- `Linux >= 773bda96492153e11d21eb63ac814669b51fc701 < aad70bdfc8244616e48c434310cab241a3f17781`\n- `Linux >= 773bda96492153e11d21eb63ac814669b51fc701 < f10d3c7267ac7387a5129d5506c3c5f2460cfd9b`\n- `Linux >= 773bda96492153e11d21eb63ac814669b51fc701 < 8bf935cf789872350b04c1a6468b0a509f67afb2`\n- `Linux 5.15`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}