CVE-2021-3347

This vulnerability allows an attacker to exploit the Linux kernel's scheduling system to insert a class into a data structure twice, potentially causing the system to enter an infinite loop and prevent packet processing. To take advantage of this, the attacker must use specific configurations with the Hierarchical Fair Service Curve (HFSC) and Token Bucket Filter (TBF) settings.

This vulnerability allows an attacker to potentially manipulate memory in the Linux kernel, which could lead to unexpected behavior or crashes in applications using the io_uring interface. It occurs when an old buffer structure is reused improperly after being emptied, which could happen under specific conditions when upgrading buffer settings.

This vulnerability allows a local attacker to potentially take control of the system or corrupt its memory by exploiting a flaw in the way the Linux kernel handles certain operations when a filesystem is being unmounted. To take advantage of this, the attacker must have local access to the system and create a specific type of operation called a futex.