CVE-2025-21699

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

gfs2: Truncate address space when flipping GFS2_DIF_JDATA flag

Truncate an inode's address space when flipping the GFS2_DIF_JDATA flag: depending on that flag, the pages in the address space will either use buffer heads or iomap_folio_state structs, and we cannot mix the two.

The bug could happen only if cluster of computers to simultaneously use a block device that is shared between them using gfs2 file system. The security impact is limited, because only corruption of this file-system could happen.

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.

To mitigate this issue, prevent module gfs2 from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.