CVE-2023-53522

published 2025-10-01

CVE-2023-53522: In the Linux kernel, the following vulnerability has been resolved: cgroup,freezer: hold cpu_hotplug_lock before freezer_mutex syzbot is reporting circular…

Priority P3 36 high 7.8 CVSS 3.1

AV L AC L PR L UI N S U C H I H A H

In the Linux kernel, the following vulnerability has been resolved:

cgroup,freezer: hold cpu_hotplug_lock before freezer_mutex

syzbot is reporting circular locking dependency between cpu_hotplug_lock
and freezer_mutex, for commit f5d39b020809 ("freezer,sched: Rewrite core
freezer logic") replaced atomic_inc() in freezer_apply_state() with
static_branch_inc() which holds cpu_hotplug_lock.

cpu_hotplug_lock => cgroup_threadgroup_rwsem => freezer_mutex

cgroup_file_write() {
cgroup_procs_write() {
__cgroup_procs_write() {
cgroup_procs_write_start() {
cgroup_attach_lock() {
cpus_read_lock() {
percpu_down_read(&cpu_hotplug_lock);
}
percpu_down_write(&cgroup_threadgroup_rwsem);
}
}
cgroup_attach_task() {
cgroup_migrate() {
cgroup_migrate_execute() {
freezer_attach() {
mutex_lock(&freezer_mutex);
(...snipped...)
}
}
}
}
(...snipped...)
}
}
}

freezer_mutex => cpu_hotplug_lock

cgroup_file_write() {
freezer_write() {
freezer_change_state() {
mutex_lock(&freezer_mutex);
freezer_apply_state() {
static_branch_inc(&freezer_active) {
static_key_slow_inc() {
cpus_read_lock();
static_key_slow_inc_cpuslocked();
cpus_read_unlock();
}
}
}
mutex_unlock(&freezer_mutex);
}
}
}

Swap locking order by moving cpus_read_lock() in freezer_apply_state()
to before mutex_lock(&freezer_mutex) in freezer_change_state().

Affected

11 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 6.1.25-1 (bookworm)	linux 6.1.25-1 (bookworm)
linux	linux	—	—
linux	linux	>= f5d39b020809146cc28e6e73369bf8065e0310aa < 3756171b97c307d9df8b8ded1d883eec30172085	3756171b97c307d9df8b8ded1d883eec30172085
linux	linux	>= f5d39b020809146cc28e6e73369bf8065e0310aa < 34fbb7b45bae20b551dda24337c7761ca13ce69d	34fbb7b45bae20b551dda24337c7761ca13ce69d
linux	linux	>= f5d39b020809146cc28e6e73369bf8065e0310aa < 57dcd64c7e036299ef526b400a8d12b8a2352f26	57dcd64c7e036299ef526b400a8d12b8a2352f26
linux	linux_kernel	—	—
linux	linux_kernel	>= 0 < 6.1.25-1	6.1.25-1
linux	linux_kernel	>= 0 < 6.1.25-1	6.1.25-1
linux	linux_kernel	>= 0 < 6.1.25-1	6.1.25-1
linux	linux_kernel	>= 6.1 < 6.1.25	6.1.25
linux	linux_kernel	>= 6.2 < 6.2.12	6.2.12

CVSS provenance

nvd v3.1 7.8 HIGH CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

osv 7.8 HIGH

vendor_debian 7.8 HIGH

vendor_redhat 7.8 HIGH

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