CVE-2022-50328

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

jbd2: fix potential use-after-free in jbd2_fc_wait_bufs

In 'jbd2_fc_wait_bufs' use 'bh' after put buffer head reference count which may lead to use-after-free. So judge buffer if uptodate before put buffer head reference count.

This issue is a use-after-free in the ext4 journaling subsystem (jbd2 fast commit path). An object (bh) was referenced after its refcount was dropped, which could result in a kernel crash or system instability. The realistic impact is a local denial of service when writing to an ext4 filesystem with fast commit enabled. The fast commit feature in ext4 is disabled by default, and it must be explicitly enabled by the system administrator (before this issue could be triggered).

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.