CVE-2024-57940

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

exfat: fix the infinite loop in exfat_readdir()

If the file system is corrupted so that a cluster is linked to itself in the cluster chain, and there is an unused directory entry in the cluster, 'dentry' will not be incremented, causing condition 'dentry < max_dentries' unable to prevent an infinite loop.

This infinite loop causes s_lock not to be released, and other tasks will hang, such as exfat_sync_fs().

This commit stops traversing the cluster chain when there is unused directory entry in the cluster to avoid this infinite loop.

This flaw is rated as Moderate severity for Red Hat Enterprise Linux because exploitation requires local access and the capability to mount a corrupted or specially crafted storage volume, limiting the blast radius to availability impact without compromising system integrity or confidentiality. In standard enterprise deployments, exFAT filesystems are not used for core operations, and mounting arbitrary external media typically requires administrative privileges or physical machine access. A successful exploit leads to an unkillable process holding filesystem locks, resulting in an unrecoverable kernel hang.

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.