CVE-2023-53845

/// Technical description

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

nilfs2: fix infinite loop in nilfs_mdt_get_block()

If the disk image that nilfs2 mounts is corrupted and a virtual block

address obtained by block lookup for a metadata file is invalid,

nilfs_bmap_lookup_at_level() may return the same internal return code as

-ENOENT, meaning the block does not exist in the metadata file.

This duplication of return codes confuses nilfs_mdt_get_block(), causing

it to read and create a metadata block indefinitely.

In particular, if this happens to the inode metadata file, ifile,

semaphore i_rwsem can be left held, causing task hangs in lock_mount.

Fix this issue by making nilfs_bmap_lookup_at_level() treat virtual block

address translation failures with -ENOENT as metadata corruption instead

of returning the error code.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References