CVE-2024-45029

What it actually does

The flaw triggers a kernel BUG by calling a mutex lock from within a spinlock-held context during runtime power management resume on ACPI systems using the Tegra I2C driver, violating atomic context rules.

Why it matters to the business

Affected Linux kernel deployments on ACPI hardware may experience sudden system crashes during power management, reducing availability; low EPSS and no KEV listing indicate limited active exploitation risk, though widespread kernel use increases patch urgency across ecosystems.

How an attack unfolds

An attacker with local access triggers __pm_runtime_resume on a Tegra I2C device, acquiring the power lock before rpm_resume invokes acpi_subsys_runtime_resume which attempts mutex operations, hitting the invalid context check and crashing the kernel.

How to fix it

Apply kernel updates containing commit a89aef1e6cc43fa019a58080ed05c839e6c77876 or equivalent stable fixes; update github.com/opencontainers/runc to version 1.1.5 where applicable; rebuild and deploy updated kernels on affected ACPI Tegra platforms.

How to confirm the fix worked

Confirm updated kernel source or binary contains the not-IRQ-safe marking change for ACPI devices; test runtime resume paths on ACPI hardware and verify absence of the mutex-in-spinlock BUG in logs.

Typical attack path

1. Obtain local access on target system
2. Perform actions that invoke runtime resume on Tegra I2C hardware
3. Trigger I2C transfer path leading to mutex acquisition under spinlock
4. Cause kernel BUG and system instability

How to detect it

Search kernel logs and dmesg for call traces containing __might_sleep, __mutex_lock_common, acpi_subsys_runtime_resume, rpm_resume, and tegra_i2c_xfer; correlate with ACPI runtime power events on Tegra platforms.

• BUG: sleeping function called from invalid context at kernel/locking/mutex.c:585
• acpi_subsys_runtime_resume
• tegra_i2c_xfer

What your security team should do

• Apply fixed kernel versions immediately on ACPI Tegra systems
• Review power management and I2C usage in custom workloads
• Monitor kernel crash reports for mutex context violations
• Track EPSS and threat actor reports for any rise in exploitation