{"id":"CVE-2026-68094","summary":"sched_ext: Preserve rq tracking across local DSQ dispatch","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Preserve rq tracking across local DSQ dispatch\n\ndispatch_to_local_dsq() can run from scx_bpf_dsq_move_to_local() while\nops.dispatch() has recorded the current rq. Moving a task to a local DSQ\nmay switch to the source or destination rq before synchronously invoking\nops.dequeue() through the following path:\n\n  SCX_CALL_OP(dispatch, rq)\n    ops.dispatch()\n      scx_bpf_dsq_move_to_local()\n        scx_flush_dispatch_buf()\n          finish_dispatch()\n            dispatch_to_local_dsq()\n              scx_dispatch_enqueue()\n                local_dsq_post_enq()\n                  call_task_dequeue()\n                    SCX_CALL_OP_TASK(dequeue, locked_rq, ...)\n\nThe nested callback saves the recorded rq and restores it on return. If\nthe rq tracking does not follow the lock switch, update_locked_rq() can\ntrigger the following lockdep assertion while restoring an rq which is\nno longer held:\n\n  WARNING: kernel/sched/sched.h:1641 at call_task_dequeue+0x160/0x170\n  Call Trace:\n    scx_dispatch_enqueue+0x2b0/0x460\n    dispatch_to_local_dsq+0x138/0x230\n    scx_flush_dispatch_buf+0x1af/0x220\n    scx_bpf_dsq_move_to_local___v2+0xe2/0x1c0\n    bpf__sched_ext_ops_dispatch+0x4b/0xa7\n    do_pick_task_scx+0x3b6/0x910\n    __pick_next_task+0x105/0x1f0\n    __schedule+0x3e7/0x1980\n\nIntroduce switch_rq_lock() to update the tracking state together with\neach rq lock handoff. Use it in dispatch_to_local_dsq(),\nmove_remote_task_to_local_dsq() and the in-balance paths of\nscx_dsq_move(), ensuring that scx_locked_rq() consistently refers to the\nrq whose lock is actually held throughout the lock dance.","modified":"2026-08-18T03:31:12.307203543Z","published":"2026-08-10T11:58:07.086Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68094.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/18d62044cda7a2b40f59d910659c0b0d6accad37"},{"type":"WEB","url":"https://git.kernel.org/stable/c/97c09c9f5739b8757ee29dabb0af30069137e286"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68094.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68094"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"7fb39e4eb4c3db52e4707a6a1cd45362f7e803f5"},{"fixed":"97c09c9f5739b8757ee29dabb0af30069137e286"},{"fixed":"18d62044cda7a2b40f59d910659c0b0d6accad37"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68094.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.1.0"},{"fixed":"7.1.6"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68094.json"}}],"schema_version":"1.9.0"}