Kernel memory corruption via premature GFS2 teardown
Published May 21, 2024 · Updated Aug 5, 2026
Use-after-free in Linux 6.6 allows local users to corrupt kernel memory by unmounting a GFS2 filesystem after quota access. In gfs2_put_super(), the read-only teardown path frees struct gfs2_sbd without running gfs2_quota_cleanup(), so the later gfs2_qd_dealloc RCU callback writes through the freed pointer. Reachability requires local ability to mount and unmount a GFS2 filesystem and issue a quota query; triggering it can crash the host or corrupt kernel memory.
Summary
What happened
Use-after-free in Linux 6.6 allows local users to corrupt kernel memory by unmounting a GFS2 filesystem after quota access. In gfs2_put_super(), the read-only teardown path frees struct gfs2_sbd without running gfs2_quota_cleanup(), so the later gfs2_qd_dealloc RCU callback writes through the freed pointer. Reachability requires local ability to mount and unmount a GFS2 filesystem and issue a quota query; triggering it can crash the host or corrupt kernel memory.
The record
- CVE
- CVE-2023-52760
- Published
- May 21, 2024
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-416, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 21, 2024CVE publishedPublication date reported by the CVE source.
- Aug 5, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=6.6
- Affected versionversion=f66af88e33212b57ea86da2c5d66c0d9d5c46344 <08a28272faa750d4357ea2cb48d2baefd778ea81
- Affected versionversion=f66af88e33212b57ea86da2c5d66c0d9d5c46344 <bdcb8aa434c6d36b5c215d02a9ef07551be25a37
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
- syzkaller C reproducer for gfs2_qd_dealloc use-after-freeproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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