In the Linux kernel, the following vulnerability has been resolved: fsnotify: Fix ordering of iput() and watched_objects decrement Ensure the superblock is kept alive until we're done with iput(). Holding a reference to an inode is not allowed unless we ensure the superblock stays alive, which fsnotify does by keeping the watched_objects count elevated, so iput() must happen before the watched_objects decrement. This can lead to a UAF of something like sb->s_fs_info in tmpfs, but the UAF is hard to hit because race orderings that oops are more likely, thanks to the CHECK_DATA_CORRUPTION() block in generic_shutdown_super(). Also, ensure that fsnotify_put_sb_watched_objects() doesn't call fsnotify_sb_watched_objects() on a superblock that may have already been freed, which would cause a UAF read of sb->s_fsnotify_info.
History

Sat, 11 Jan 2025 12:30:00 +0000

Type Values Removed Values Added
References

Sat, 14 Dec 2024 02:15:00 +0000

Type Values Removed Values Added
Metrics threat_severity

Important

threat_severity

Moderate


Fri, 13 Dec 2024 14:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Mon, 09 Dec 2024 14:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Important


Sat, 07 Dec 2024 07:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: fsnotify: Fix ordering of iput() and watched_objects decrement Ensure the superblock is kept alive until we're done with iput(). Holding a reference to an inode is not allowed unless we ensure the superblock stays alive, which fsnotify does by keeping the watched_objects count elevated, so iput() must happen before the watched_objects decrement. This can lead to a UAF of something like sb->s_fs_info in tmpfs, but the UAF is hard to hit because race orderings that oops are more likely, thanks to the CHECK_DATA_CORRUPTION() block in generic_shutdown_super(). Also, ensure that fsnotify_put_sb_watched_objects() doesn't call fsnotify_sb_watched_objects() on a superblock that may have already been freed, which would cause a UAF read of sb->s_fsnotify_info.
Title fsnotify: Fix ordering of iput() and watched_objects decrement
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-12-07T06:40:43.522Z

Updated: 2025-01-11T12:23:40.753Z

Reserved: 2024-11-19T17:17:24.997Z

Link: CVE-2024-53143

cve-icon Vulnrichment

Updated: 2024-12-11T14:22:09.680Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2024-12-07T07:15:03.780

Modified: 2025-01-11T13:15:25.250

Link: CVE-2024-53143

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-12-07T00:00:00Z

Links: CVE-2024-53143 - Bugzilla