CVE-2023-52498

What it actually does

The flaw allows async_schedule_dev() to fall back to synchronous execution of device suspend/resume callbacks while mutexes are already held, creating deadlock conditions or violating device dependency ordering during system-wide PM transitions under memory pressure.

Why it matters to the business

Systems may hang or become unavailable during resume from sleep when memory is low, disrupting operations and requiring manual intervention or reboot.

How an attack unfolds

An attacker with local access creates low-memory conditions then triggers suspend/resume cycles; the synchronous fallback path inside dpm_async_fn() acquires an already-held mutex or runs a consumer resume before its supplier, deadlocking the PM core.

How to fix it

Upgrade the Linux kernel to a version containing commit f46eb832389f162ad13cb780d0b8cde93641990d or later; rebuild and reboot into the patched kernel.

How to confirm the fix worked

Confirm the running kernel includes commit f46eb832389f162ad13cb780d0b8cde93641990d via git log or kernel version string; attempt low-memory suspend/resume cycles in a test environment and verify no deadlock occurs.

Typical attack path

1. Gain local access to the system
2. Exhaust available memory to force async fallback
3. Initiate system suspend followed by resume
4. Trigger repeated PM transitions to increase likelihood of deadlock

How to detect it

Review kernel logs for PM core deadlock messages or hung task warnings during resume; examine dmesg and syslog around suspend/resume events for ordering or mutex contention indicators.

What your security team should do

• Prioritize kernel upgrade on all affected Linux systems within standard change windows
• Test patched kernels under simulated low-memory PM scenarios before broad deployment
• Monitor vendor advisories for backported fixes in distribution kernels