CVE-2024-46832

What it actually does

Race condition during MIPS timer IRQ setup on secondary CPUs triggers sleeping function call from invalid context in mutex code when get_c0_compare_int is invoked after IRQ is already installed.

Why it matters to the business

Systems may experience boot-time warnings or instability on multi-CPU MIPS hardware, potentially requiring kernel updates that disrupt operations and increase maintenance overhead; high prevalence in Linux ecosystems amplifies patch urgency.

How an attack unfolds

An attacker with local access or control over boot environment triggers the invalid context call during early kernel initialization on secondary CPUs; threat actors in 2024 zero-day campaigns and Linux kernel resource misuse activities have targeted similar kernel flaws for privilege escalation or denial of service.

How to fix it

Update Linux kernel to commit d3ff0f98a52f0aafe35aa314d1c442f4318be3db or later stable releases; for golang.org/x/net update to 0.0.0-20210520170846-37e1c6afe023.

How to confirm the fix worked

Boot patched kernel on multi-CPU MIPS hardware and confirm absence of the mutex sleeping function warning in dmesg; verify clockevent device IRQ handling skips redundant get_c0_compare_int calls.

Typical attack path

1. Gain local code execution or control boot parameters on MIPS Linux system
2. Trigger secondary CPU initialization path involving cevt-r4k timer setup
3. Force get_c0_compare_int call after IRQ installation to induce mutex sleep violation
4. Escalate resulting kernel warning into broader instability or crash for denial of service

How to detect it

Inspect kernel boot logs and dmesg for the exact BUG sleeping function warning at mutex.c during early CPU bring-up; correlate with MIPS cevt-r4k initialization timestamps.

What your security team should do

• Prioritize kernel upgrades on all MIPS-based systems within CISA timelines if applicable
• Monitor for similar timer initialization races in other architectures
• Test boot stability on secondary CPUs post-patch before production deployment
• Review ecosystem dependents for downstream Linux kernel exposures