CVE-2024-42223

What it actually does

Integer overflow in 32-bit calculation of xtal_hz multiplied by pll_mfactor when xtal_hz reaches up to 16M, producing incorrect intermediate results during DVB frontend PLL configuration.

Why it matters to the business

Potential kernel instability or denial of service on Linux systems using affected DVB hardware, increasing operational risk for media and broadcast workloads until kernels are updated.

How an attack unfolds

An attacker with local access supplies or triggers DVB frontend initialization code that performs the 32-bit multiplication; the resulting overflow leads to invalid hardware state and subsequent failure or crash in the media subsystem.

How to fix it

Upgrade the Linux kernel to a version containing commit 8167e4d7dc086d4f7ca7897dcff3827e4d22c99a or later; rebuild and deploy the updated kernel image across all affected systems.

How to confirm the fix worked

Confirm the running kernel source contains the 64-bit variable change for the xtal_hz * pll_mfactor calculation; test DVB frontend initialization with maximum xtal_hz values to verify no overflow occurs.

Typical attack path

1. Obtain local code execution or user privileges on a Linux system with the vulnerable tda10048 driver loaded
2. Trigger DVB frontend attach or tuning operations that load state->xtal_hz and perform the pll_mfactor multiplication
3. Cause the 32-bit integer overflow during calculation
4. Observe resulting invalid PLL values leading to driver malfunction or kernel fault

How to detect it

Review kernel logs for media or DVB frontend errors during device initialization; look for unexpected crashes or invalid frequency calculations in systems using the tda10048 driver.

What your security team should do

• Prioritize kernel updates on any systems exposing DVB or media subsystems
• Audit deployed kernels for the presence of the vulnerable tda10048 driver code
• Monitor for local privilege-escalation attempts targeting media drivers until patches are applied