{"id":"CVE-2026-98865","summary":"sched_ext: Don't run ops.dequeue() with a DSQ lock held","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Don't run ops.dequeue() with a DSQ lock held\n\nops.dequeue() is invoked with the source user DSQ's lock still held on\nthe consume and move paths (scx_consume_dispatch_q(),\nmove_task_between_dsqs()). A BPF scheduler which locks the source user\nDSQ from ops.dequeue() - e.g. by iterating it with bpf_iter_scx_dsq -\nself-deadlocks.\n\nops.dequeue() can only call the \"any\" kfuncs and none of them can lock a\nbuiltin DSQ, so the global and bypass paths can't deadlock; however,\nall DSQ locks share one lockdep class, so iterating any user DSQ from\nops.dequeue() on those paths trips the recursion check.\n\nMove the invocation after the DSQ unlock on all three paths.\nSCX_TASK_IN_CUSTODY is cleared under the lock serializing the transfer\nso that the callback is invoked exactly once.","modified":"2026-10-19T02:47:36.132638179Z","published":"2026-10-18T15:51:26.449Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98865.json","cna_assigner":"Linux"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cb86607ada73185f321baa7f9d94a08a3a40bbf5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fe499ae9da46e297f578d4346c4c8e338c3118db"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98865.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98865"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"ebf1ccff79c43f860cbd2f9d6cfab9a462d0cb2d"},{"fixed":"fe499ae9da46e297f578d4346c4c8e338c3118db"},{"fixed":"cb86607ada73185f321baa7f9d94a08a3a40bbf5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98865.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.1.0"},{"fixed":"7.2.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98865.json"}}],"schema_version":"1.9.0"}