AZL-97769

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

Input: byd - synchronize timer deletion before freeing private data

byddisconnect() uses timerdelete() before freeing the driver's private data. This does not wait for a running bydcleartouch() callback, which dereferences the private data and its psmouse pointer. A callback racing with disconnect can therefore access the private data after it has been freed. The timer can also still be re-armed by bydprocessbyte() while the disconnect is in progress.

Use timershutdownsync() before freeing the private data: it waits for a running callback and turns any later re-arm attempt into a no-op.