CVE-2024-47757

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

nilfs2: fix potential oob read in nilfs_btree_check_delete()

The function nilfs_btree_check_delete(), which checks whether degeneration to direct mapping occurs before deleting a b-tree entry, causes memory access outside the block buffer when retrieving the maximum key if the root node has no entries.

This does not usually happen because b-tree mappings with 0 child nodes are never created by mkfs.nilfs2 or nilfs2 itself. However, it can happen if the b-tree root node read from a device is configured that way, so fix this potential issue by adding a check for that case.

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.