CVE-2026-90422: clk: mediatek: pllfh: Fix IO remapping leak in register_pllfhs error path

Severity: unknown
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-17 · updated 2026-10-21

Description

In the Linux kernel, the following vulnerability has been resolved: clk: mediatek: pllfh: Fix IO remapping leak in register_pllfhs error path When mtk_clk_register_pllfhs function fails to register a PLL, it unregisters all PLLs and cleans up itself in its error path before returning, so the function callers don't need to do it. But contrary to mtk_clk_unregister_pllfhs function, that does almost the same sequence, it does not free the IO memory mapped on fhctl node, leading to a leak. Fix this leak by factorizing the cleanup sequence in a new private function and use it both mtk_clk_register_pllfhs and mtk_clk_unregister_pllfhs functions. Also, change the loop index start value to avoid the -1 operation on index at each loop.

Affected products

Linux kernel: 6.2 — fixed in 7.3

How to fix

Upgrade to a fixed version: Linux kernel 7.3. Check the vendor advisory for mitigations.

References

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