CVE-2026-89721

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

phy: rockchip-samsung-dcphy: fix out-of-range max_register

The PHY register block is 64KB, so with a register stride of 4 the

last accessible register sits at offset 0xfffc. max_register names

0x10000, one register past the end of the mapping: dumping the

registers through the regmap debugfs interface reads beyond the

ioremapped region and oopses on the unmapped page. The oops fires

with the regmap lock held, so later PHY operations deadlock.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References