CVE-2026-90335

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

tty: skip cdev_del() when no cdev is registered

TTY device registration can fail before a cdev is allocated.
Serial core keeps the port so setserial can still use it, and later
removal passes the NULL cdev slot to cdev_del(), causing a NULL-pointer
dereference.

Only delete the cdev when the slot is not NULL.