CVE-2026-53384serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails

Official description

In the Linux kernel, the following vulnerability has been resolved: serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails dw8250_probe() registers the 8250 port via serial8250_register_8250_port() and then, if the device has a clock, registers a clock notifier. If clk_notifier_register() fails, probe returns the error but leaves the 8250 port registered. The matching serial8250_unregister_port() lives in dw8250_remove(), which is not called when probe fails, so the port slot stays occupied until the device is rebound or the system is rebooted. The devm-allocated driver data is freed while the port still references it (via the saved private_data and serial_in/serial_out callbacks), so any access to that port slot before a rebind is a use-after-free hazard. Unregister the port on the clk_notifier_register() error path.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/ccdf4510a3873b14e5e348cdb038717996f09fda
• https://git.kernel.org/stable/c/511d2b92f8d20de04acafab676150d26fb5c67f4
• https://git.kernel.org/stable/c/07ffe414a708ae60551401cec5d727ed156b8caf
• https://git.kernel.org/stable/c/3d205fe80f2181f0109150ad1fa06ee5bc046935
• https://git.kernel.org/stable/c/d72650a4f334581b23a1892b888a4cb1be142f76
• https://git.kernel.org/stable/c/778b9dda4b24005a27bcd9c35c110bf8d7f259ca
• https://git.kernel.org/stable/c/10fc708b4de7f86002d2d735a2dbf3b5b7f65692