Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix incorrect FI_NO_EXTENT handling in __destroy_extent_node() When __destroy_extent_node() sets the inode flag FI_NO_EXTENT, it does not reset the length of the largest extent to 0 and update the inode folio. Since modifications to the extent tree are disallowed afterward, the cached largest extent may become stale. This can trigger the following error in xfstests generic/388: F2FS-fs (dm-0): sanity_check_extent_cache: inode (ino=1761) extent info [220057, 57, 6] is incorrect, run fsck to fix In the f2fs_drop_inode path, __destroy_extent_node() does not need to guarantee that et->node_cnt is 0, because concurrency with writeback is expected in this path, and writeback may update the extent cache. This patch reverts commit ed78aeebef05 ("f2fs: fix node_cnt race between extent node destroy and writeback"), and remove the unnecessary zero check of et->node_cnt.
CVSS Score
HIGH
References
- https://git.kernel.org/stable/c/1f70ddb28a3c71df124da5fa4040c808116d6bb9
- https://git.kernel.org/stable/c/20190e498057997532c7f186d081011f18e0a462
- https://git.kernel.org/stable/c/58a5deb220bcac4c73bf58954c0845644c997487
- https://git.kernel.org/stable/c/7e4d8f98be63f98856a5176b9188dada6e7ba9ee
- https://git.kernel.org/stable/c/edf12cbeeeabe799bd2ee21fdb5c336cce6fbad7
FAQ
What is CVE-2026-63812?
CVE-2026-63812 is a vulnerability with a CVSS score of 7.8 (HIGH). In the Linux kernel, the following vulnerability has been resolved: f2fs: fix incorrect FI_NO_EXTENT handling in __destroy_extent_node() When __destroy_extent_node() sets the inode flag FI_NO_EXTENT...
How severe is CVE-2026-63812?
CVE-2026-63812 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-63812?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.