{"id":"CVE-2023-53522","summary":"cgroup,freezer: hold cpu_hotplug_lock before freezer_mutex","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ncgroup,freezer: hold cpu_hotplug_lock before freezer_mutex\n\nsyzbot is reporting circular locking dependency between cpu_hotplug_lock\nand freezer_mutex, for commit f5d39b020809 (\"freezer,sched: Rewrite core\nfreezer logic\") replaced atomic_inc() in freezer_apply_state() with\nstatic_branch_inc() which holds cpu_hotplug_lock.\n\ncpu_hotplug_lock =\u003e cgroup_threadgroup_rwsem =\u003e freezer_mutex\n\n  cgroup_file_write() {\n    cgroup_procs_write() {\n      __cgroup_procs_write() {\n        cgroup_procs_write_start() {\n          cgroup_attach_lock() {\n            cpus_read_lock() {\n              percpu_down_read(&cpu_hotplug_lock);\n            }\n            percpu_down_write(&cgroup_threadgroup_rwsem);\n          }\n        }\n        cgroup_attach_task() {\n          cgroup_migrate() {\n            cgroup_migrate_execute() {\n              freezer_attach() {\n                mutex_lock(&freezer_mutex);\n                (...snipped...)\n              }\n            }\n          }\n        }\n        (...snipped...)\n      }\n    }\n  }\n\nfreezer_mutex =\u003e cpu_hotplug_lock\n\n  cgroup_file_write() {\n    freezer_write() {\n      freezer_change_state() {\n        mutex_lock(&freezer_mutex);\n        freezer_apply_state() {\n          static_branch_inc(&freezer_active) {\n            static_key_slow_inc() {\n              cpus_read_lock();\n              static_key_slow_inc_cpuslocked();\n              cpus_read_unlock();\n            }\n          }\n        }\n        mutex_unlock(&freezer_mutex);\n      }\n    }\n  }\n\nSwap locking order by moving cpus_read_lock() in freezer_apply_state()\nto before mutex_lock(&freezer_mutex) in freezer_change_state().","modified":"2026-08-12T03:51:31.903415882Z","published":"2025-10-01T11:46:08.909Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53522.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/34fbb7b45bae20b551dda24337c7761ca13ce69d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3756171b97c307d9df8b8ded1d883eec30172085"},{"type":"WEB","url":"https://git.kernel.org/stable/c/57dcd64c7e036299ef526b400a8d12b8a2352f26"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53522.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-53522"},{"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":"f5d39b020809146cc28e6e73369bf8065e0310aa"},{"fixed":"3756171b97c307d9df8b8ded1d883eec30172085"},{"fixed":"34fbb7b45bae20b551dda24337c7761ca13ce69d"},{"fixed":"57dcd64c7e036299ef526b400a8d12b8a2352f26"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53522.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.1.0"},{"fixed":"6.1.25"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.2.12"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53522.json"}}],"schema_version":"1.9.0"}