CVE-2026-90336

About vulnerability

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

serial: core: clear freed pointers on uart_register_driver() failure

uart_register_driver() leaves drv->state pointing to freed memory when tty_alloc_driver() fails. If tty_register_driver() fails, drv->tty_driver also retains a pointer after its reference is dropped.

Drivers that use drv->state as an “already registered” flag can then skip registration on the next probe and pass the freed state to uart_add_one_port().

This issue was found with failslab on QEMU’s raspi1ap board by failing registration and binding the PL011 port again.

Clear both pointers on their failure paths, as uart_unregister_driver() already does.

Affected product:

AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS

Affected packages:

linux @ 5.10.259 (+19 more)