CVE-2023-52858

What it actually does

Missing NULL check after mtk_alloc_clk_data() in the MediaTek MT7629 clock driver allows a failed allocation to result in immediate NULL pointer dereference during clock initialization.

Why it matters to the business

Systems using the affected MediaTek SoC may crash or fail to boot reliably, causing unplanned downtime and requiring physical or console intervention to recover.

How an attack unfolds

An attacker with the ability to trigger early kernel initialization on affected hardware (for example via crafted boot parameters or hardware fault injection) can induce allocation failure, leading to a kernel oops and denial of service. No remote unauthenticated path exists; local or physical access is required.

How to fix it

Update the Linux kernel to a version containing commit e8ae4b49dd9cfde69d8de8c0c0cd7cf1b004482e or later. Rebuild and deploy the updated kernel image on all affected MediaTek MT7629 platforms.

How to confirm the fix worked

Confirm the presence of the fix commit in the kernel source tree or verify that the clk-mt7629 probe function now checks the return value of mtk_alloc_clk_data() before use.

Typical attack path

1. Gain local or physical access to an affected device
2. Trigger kernel boot or clock subsystem initialization
3. Cause mtk_alloc_clk_data() to return NULL (resource exhaustion or fault)
4. Execute the unchecked dereference path in clk-mt7629
5. Induce kernel panic or hang

How to detect it

Search kernel logs and dmesg output for NULL pointer dereference panics originating from the clk-mt7629 driver during early boot; correlate with device model identifiers indicating MT7629 hardware.

• Unable to handle kernel NULL pointer dereference
• clk-mt7629
• mtk_alloc_clk_data

What your security team should do

• Prioritize kernel upgrade on all MT7629-based devices within standard maintenance windows
• Test the updated kernel in a lab environment for boot stability before broad rollout
• Monitor kernel logs for NULL pointer dereference oops referencing clk-mt7629 during boot