CVE-2024-57942: netfs: Fix ceph copy to cache on write-begin
In the Linux kernel, the following vulnerability has been resolved:
netfs: Fix ceph copy to cache on write-begin
At the end of netfsunlockreadfolio() in which folios are marked appropriately for copying to the cache (either with by being marked dirty and having their private data set or by having PGprivate2 set) and then unlocked, the folioqueue struct has the entry pointing to the folio cleared. This presents a problem for netfspgpriv2writetothecache(), which is used to write folios marked with PGprivate2 to the cache as it expects to be able to trawl the folioqueue list thereafter to find the relevant folios, leading to a hang.
Fix this by not clearing the folioqueue entry if we're going to do the deprecated copy-to-cache. The clearance will be done instead as the folios are written to the cache.
This can be reproduced by starting cachefiles, mounting a ceph filesystem with "-o fsc" and writing to it.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2024-57942?
The severity of CVE-2024-57942 has not been explicitly reported, but it addresses vulnerabilities in the Linux kernel's netfs subsystem.
How do I fix CVE-2024-57942?
To fix CVE-2024-57942, you should update your Linux kernel to the latest stable version provided by your distribution.
What systems are affected by CVE-2024-57942?
CVE-2024-57942 affects systems running vulnerable versions of the Linux kernel that utilize the netfs framework.
Is CVE-2024-57942 exploitable remotely?
There is currently no information indicating that CVE-2024-57942 is remotely exploitable, as it relates to the handling of data internally in the kernel.
When was CVE-2024-57942 announced?
CVE-2024-57942 was resolved in recent updates, but the exact announcement date is not specified in the provided information.