In the Linux kernel, the following vulnerability has been resolved: tty: abort break signalling on hangup The break ioctls can race with hangup and end up calling into a tty driver for a device that is already gone or powered down. Drivers must handle this race, but TCSBRK and TCSBRKP should still be aborted to avoid calling back into the driver after a user-controlled timeout (possibly even after the tty has been reopened). Note that drivers should disable any break state on shutdown so just return on hangup (calling break_ctl() again is racy and will most likely fail for drivers handling the race).
https://git.kernel.org/stable/c/c8ccd3b2013daaf77b98f8a6724fcf4d2c5c52d6
https://git.kernel.org/stable/c/94af6cd832e9b4ce39a8fb59144a8f09ab56fd35
https://git.kernel.org/stable/c/845a2737e0f5ffe5ca8d38de556012b0c9472cdd
https://git.kernel.org/stable/c/3bc82999fb85cecc7eb6ec1755ee7d698aa1e783