{"id":"CVE-2026-99104","aliases":[],"title":"sched_ext: Fix the bypass dispatch claim for schedulers bypassed by an ancestor","titleSource":"Linux","descriptionSource":"Linux","products":[{"vendor":"Linux","name":"Linux","platforms":[],"versions":[{"version":"aa2a0a19686c90106ade6a7e848ffbb62d55d733","status":"affected","lessThan":"f0f18075e45d47bef7ff2eb9512ee4f0c7e5f9c7","versionType":"git"},{"version":"aa2a0a19686c90106ade6a7e848ffbb62d55d733","status":"affected","lessThan":"5bdeca322a6f8d10acaf67cccab1f69747ee7be3","versionType":"git"}],"defaultStatus":"unaffected","source":"Linux","url":"https://www.cve.org/CVERecord?id=CVE-2026-99104"},{"vendor":"Linux","name":"Linux","platforms":[],"versions":[{"version":"7.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"7.1","versionType":"semver"},{"version":"7.2.13","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"defaultStatus":"affected","source":"Linux","url":"https://www.cve.org/CVERecord?id=CVE-2026-99104"}],"remediation":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Fix the bypass dispatch claim for schedulers bypassed by an ancestor\n\nscx_bypass() claims bypass dispatch when the scheduler's depth goes from\nzero to one and releases it when the depth returns to zero, but propagates\nonly the depth to the descendants, not the claim. A descendant that starts\nbypassing with its ancestor never claims, and one whose own bypass ends\nunder the ancestor's keeps its claim, as its depth does not return to zero.\n\nA sub-scheduler enable whose bypass ends under a PM suspend thus leaks its\nclaim: the parent keeps hosting bypass dispatch and the sub-scheduler's next\nbypass trips the WARN_ON_ONCE() on the claim. A sub-scheduler disable that\nstarts under a PM suspend has no claim, so once the resume lifts the root's\nbypass its tasks sit on the parent's bypass DSQs with nobody consuming them.\n\nClaim for every descendant whose depth goes from zero to one in the\npropagation and release every scheduler in the subtree whose depth returned\nto zero once the tasks have moved out of the bypass DSQs. A parent that is\nbypassing itself when a descendant claims consumes only its own bypass DSQs,\nempty until it leaves bypass and becomes the host.","severity":"unknown","score":null,"published":"2026-10-28T10:34:23.729Z","modified":"2026-10-28T10:34:23.729Z","withdrawn":false,"knownExploited":false,"affected":[],"references":["https://git.kernel.org/stable/c/f0f18075e45d47bef7ff2eb9512ee4f0c7e5f9c7","https://git.kernel.org/stable/c/5bdeca322a6f8d10acaf67cccab1f69747ee7be3"],"sources":[{"name":"CVE","id":"CVE-2026-99104","modified":"2026-10-28T10:34:23.729Z","url":"https://www.cve.org/CVERecord?id=CVE-2026-99104"}],"assessments":[],"sourceAffected":[],"kev":{"status":"not-listed","checkedAt":"2026-10-28T15:40:31.878Z"},"coverage":[{"source":"NVD","status":"not-checked"},{"source":"GHSA","status":"not-checked"},{"source":"EUVD","status":"not-checked"},{"source":"EPSS","status":"not-checked"}],"evidence":[]}