kernel: fget: check that the fd still exists after getting a ref to it

A read-after-free memory flaw was found in the Linux kernel's garbage collection for Unix domain socket file handlers in the way users call close and fget simultaneously and can potentially trigger a race condition. This flaw allows a local user to crash the system or escalate their privileges on...

PT-2021-1523 · Linux +11 · Linux Kernel +11

Name of the Vulnerable Software and Affected Versions: Linux kernel versions prior to 5.16-rc4 Description: A read-after-free memory flaw was found in the Linux kernel's garbage collection for Unix domain socket file handlers. This issue occurs when users call close and fget simultaneously,...