PT-2024-6363 · Linux+6 · Linux Kernel+6
Published
2024-07-03
·
Updated
2026-03-13
·
CVE-2024-42241
CVSS v3.1
5.5
Medium
| Vector | AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Name of the Vulnerable Software and Affected Versions
Linux kernel versions prior to 6.10.0-rc5-gavin+
Description
The issue is related to the
mm/shmem module in the Linux kernel, where PMD-sized page cache can't be supported by xarray for shmem files, leading to errors when the xarray entry is split. This can occur, for example, with a 512MB page cache on ARM64 when the base page size is 64KB. The problem arises because the page cache in a shmem file isn't represented by a multi-index entry, which doesn't have this limitation when the xarray entry is split until a specific commit. The vulnerability can cause system crashes or errors, as indicated by warning messages when the xarray entry is split.Recommendations
To resolve the issue, disable PMD-sized page cache when
HPAGE PMD ORDER is larger than MAX PAGECACHE ORDER. This can be achieved by applying the fix mentioned, which involves disabling PMD-sized page cache under the specified conditions.Note: The provided information does not specify the exact version where the issue is fixed, but it mentions that the problem is resolved by disabling PMD-sized page cache when
HPAGE PMD ORDER is larger than MAX PAGECACHE ORDER, as pointed out by Matthew Wilcox, until commit 6b24ca4a1a8d ("mm: Use multi-index entries in the page cache").Exploit
Fix
Allocation of Resources Without Limits
Found an issue in the description? Have something to add? Feel free to write us 👾
Weakness Enumeration
Related Identifiers
Affected Products
Alt Linux
Astra Linux
Debian
Linuxmint
Linux Kernel
Suse
Ubuntu