CVE-2023-52876

What it actually does

Missing validation of the return value from mtk_alloc_clk_data() allows a subsequent NULL pointer dereference in the MediaTek MT7629 Ethernet clock driver.

Why it matters to the business

Kernel instability or crash on affected embedded devices can interrupt network services and require manual recovery or reboot.

How an attack unfolds

An attacker with the ability to induce memory allocation failure during driver initialization triggers the unchecked NULL return, resulting in a kernel oops or panic; no remote code execution path is known.

How to fix it

Apply the upstream fix in commit cfa68e0ac5dcde43577adadf6f0f26f3b365ad68 or later; rebuild and deploy kernels containing the added NULL check for all affected MediaTek MT7629 platforms.

How to confirm the fix worked

Confirm the presence of the NULL-pointer check after mtk_alloc_clk_data() in clk-mt7629-eth.c; test driver initialization under simulated allocation failure.

Typical attack path

1. Gain local access or trigger driver load on a vulnerable kernel build
2. Exhaust memory resources to force mtk_alloc_clk_data() to return NULL
3. Allow the driver to dereference the NULL pointer during clock registration
4. Observe kernel crash or denial of service

How to detect it

Review kernel logs for oops or panic messages originating from clk-mt7629-eth.c; correlate with boot-time allocation failures on MT7629 hardware.

• Unable to allocate clk data for eth
• clk-mt7629-eth
• mtk_alloc_clk_data

What your security team should do

• Prioritize kernel updates on all MT7629-based devices within standard maintenance windows
• Monitor for kernel oops reports referencing clk-mt7629-eth during boot or network bring-up
• Restrict unprivileged local access on embedded systems until patched