Linux Kernel F2FS Filesystem Data Block Allocation Vulnerability

A vulnerability in the Linux kernel's F2FS (Flash-Friendly File System) has been identified, related to improper sanity checks on total data blocks. This issue arises when the checkpoint's valid block count does not align with the Segment Information Table (SIT), leading to a kernel panic during garbage collection. The F2FS allocator fails to find free segments, causing the system to crash. The vulnerability has been addressed by implementing a consistency check between the checkpoint's valid block count and the blocks accounted for in the SIT.

Impact

Exploitation of this vulnerability leads to a kernel panic, causing a system crash.