PT-2025-18551 · Linux+2 · Linux Kernel+2
Published
2022-11-08
·
Updated
2025-07-10
·
CVE-2022-49834
CVSS v3.1
7.8
High
| Vector | AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Name of the Vulnerable Software and Affected Versions
Linux kernel (affected versions not specified)
Description
A use-after-free bug has been identified in the nilfs2 filesystem. This issue occurs when a nilfs2 filesystem is downgraded to read-only due to metadata corruption on disk and is remounted read/write, or if an emergency read-only remount is performed. In these cases, detaching a log writer and synchronizing the filesystem can happen simultaneously, leading to a use-after-free scenario. The bug is caused by the log writer (nilfs->ns writer) being freed by one task while another task is still accessing it. This patch fixes the issue by not detaching nilfs->ns writer on remount, preventing the UAF race.
Recommendations
To resolve this issue, apply the patch that fixes the use-after-free bug by not detaching nilfs->ns writer on remount. Additionally, consider inserting necessary read-only checks with the superblock instance to ensure the filesystem is handled correctly.
At the moment, there is no information about a newer version that contains a fix for this vulnerability.
Exploit
Use After Free
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Weakness Enumeration
Related Identifiers
Affected Products
Astra Linux
Linux Kernel
Suse