{"id":"CVE-2026-80916","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nkcov: fix data corruption and race conditions on PREEMPT_RT\n\nsyzbot is reporting KCOV state corruption on PREEMPT_RT kernels, for the\ntemporary storage used for saving/…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nkcov: fix data corruption and race conditions on PREEMPT_RT\n\nsyzbot is reporting KCOV state corruption on PREEMPT_RT kernels, for the\ntemporary storage used for saving/…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 < ef7048d8a614c5f5a9b20513a5428101a744514e","Linux >= 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 < 8ed3ddf23d39bf5338406bd9f8863d44748cf6ce","Linux >= 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 < 5dc59fc959b2b5742985d7ef24bccd1868217dc2","Linux >= 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 < a2fb8222cde23b0001812ed3acb7c0ea36dd94e2","Linux >= 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 < 18799e858b407bf355383c9dd6c06477aa437134","Linux >= 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 < e11f5b48c82703242a3be7a7ae4b4940b4cb4610","Linux >= 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 < 22670d1552fe155822b2abf91f920925f7d067b4","Linux >= 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 < f8c9a3ec36b4ee3d4701b9be08f40e7bfbf89761","Linux >= 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 < 2eed77fdcb0cc48e8eccb2bcd4b7f2c6d650e84c","Linux 5.8"],"published":"2026-09-09","updated":"2026-09-09","sourceUpdated":"2026-09-09T17:17:46.513","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-80916","references":[{"url":"https://git.kernel.org/stable/c/18799e858b407bf355383c9dd6c06477aa437134","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/22670d1552fe155822b2abf91f920925f7d067b4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2eed77fdcb0cc48e8eccb2bcd4b7f2c6d650e84c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5dc59fc959b2b5742985d7ef24bccd1868217dc2","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8ed3ddf23d39bf5338406bd9f8863d44748cf6ce","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a2fb8222cde23b0001812ed3acb7c0ea36dd94e2","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e11f5b48c82703242a3be7a7ae4b4940b4cb4610","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ef7048d8a614c5f5a9b20513a5428101a744514e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f8c9a3ec36b4ee3d4701b9be08f40e7bfbf89761","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-09T17:16:03.094Z","epss":0.00182,"epssPercentile":0.07974,"slug":"CVE-2026-80916","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nkcov: fix data corruption and race conditions on PREEMPT_RT\n\nsyzbot is reporting KCOV state corruption on PREEMPT_RT kernels, for the\ntemporary storage used for saving/restoring remote KCOV state is currently\nallocated as the per-CPU area.\n\nOn PREEMPT_RT kernels, softirq handlers run as preemptible task threads\n(e.g., ksoftirqd). If a softirq context preempts a task running a remote\nKCOV session, it safely saves the task's state into the per-CPU area.\nHowever, if that softirq thread is subsequently preempted by a higher-\npriority softirq thread on the same CPU, the second softirq will overwrite\nthe same per-CPU area, permanently destroying the original task's KCOV\nstate.\n\nFix this data corruption by moving the temporary storage from the per-CPU\narea to the per-thread area. Since each softirq thread now owns its own\ntask context, nested softirq preemption no longer causes data overwrites.\n\nNote that while the temporary storage is now on a per-thread basis, the\nper-CPU kcov_percpu_data.lock must be retained, for we need to ensure that\nkcov_remote_start() and kcov_remote_stop() operate atomically without\nracing against asynchronous interrupts that manipulate the current task's\nKCOV state.\n\nIt is likely that GFP_KERNEL allocation by vmalloc_node() in kcov_init()\nhas already called panic() before returning NULL, for there will be no\nOOM-killable userspace processes when __init function of built-in module\nruns. But this patch also fixes crashing the kernel when vmalloc_node()\nin kcov_init() returned NULL, for kcov_init() left per-CPU irq_area == NULL\nbut kcov_remote_start() depends on per-CPU irq_area != NULL, resulting in\n\n  (1) doing vmalloc() in kcov_remote_start() despite !in_task() context\n\n  (2) out-of-array-bounds access if (1) succeeded but\n      kcov->remote_size < CONFIG_KCOV_IRQ_AREA_SIZE\n\n  (3) always leak memory allocated by (1), eventually killing all\n      OOM-killable userspace processes\n\nproblems.\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":[]}