Kernel crash via delayed-iput teardown race
Published Jul 25, 2025 · Updated May 11, 2026
Race condition in Linux 6.15 Btrfs allows local users to crash the kernel by racing metadata reclaim with filesystem unmount. In close_ctree(), the kernel sets BTRFS_FS_STATE_NO_DELAYED_IPUT before canceling async reclaim work, so a worker later calls btrfs_add_delayed_iput() and hits an assertion. Low-privileged local access and precise timing during Btrfs writeback and unmount are required; the reported consequence is a kernel crash.
Summary
What happened
Race condition in Linux 6.15 Btrfs allows local users to crash the kernel by racing metadata reclaim with filesystem unmount. In close_ctree(), the kernel sets BTRFS_FS_STATE_NO_DELAYED_IPUT before canceling async reclaim work, so a worker later calls btrfs_add_delayed_iput() and hits an assertion. Low-privileged local access and precise timing during Btrfs writeback and unmount are required; the reported consequence is a kernel crash.
The record
- CVE
- CVE-2025-38358
- Published
- Jul 25, 2025
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-362, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 25, 2025CVE publishedPublication date reported by the CVE source.
- May 11, 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?
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- Affected versionversion=19e60b2a95f5d6b77d972c7bec35a11e70fd118c <4693cda2c06039c875f2eef0123b22340c34bfa0
- Affected versionversion=19e60b2a95f5d6b77d972c7bec35a11e70fd118c <a26bf338cdad3643a6e7c3d78a172baadba15c1a
- Affected versionversion=6.15
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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Your stack
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