Kernel warning via ext4 reference-count leak
Published Jun 25, 2024 · Updated May 23, 2026
Resource-management error in Linux ext4 allows local users to trigger a kernel warning while an ext4 filesystem is unmounted. In ext4_xattr_block_cache_find(), an -ENOMEM return from ext4_sb_bread() leaves the reference acquired by __entry_find() unreleased. Triggering the reported path requires local access to exercise ext4 extended-attribute lookup, reach the allocation-failure branch, and initiate filesystem teardown; the documented consequence is a warning from mb_cache_destroy.
Summary
What happened
Resource-management error in Linux ext4 allows local users to trigger a kernel warning while an ext4 filesystem is unmounted. In ext4_xattr_block_cache_find(), an -ENOMEM return from ext4_sb_bread() leaves the reference acquired by __entry_find() unreleased. Triggering the reported path requires local access to exercise ext4 extended-attribute lookup, reach the allocation-failure branch, and initiate filesystem teardown; the documented consequence is a warning from mb_cache_destroy.
The record
- CVE
- CVE-2024-39276
- Published
- Jun 25, 2024
- Updated
- May 23, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 25, 2024CVE publishedPublication date reported by the CVE source.
- May 23, 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=4.14.92 <4.15
- Affected versionversion=4.19.14 <4.19.316
- Affected versionversion=4.20.1 <4.21
- Affected versionversion=5.0
- Affected versionversion=81313ed2c705d958744882a269bf4a5e3ddec95e
- Affected versionversion=9da1f6d06b7a6d068e68fcfd7cbbf6b586d888e1
- Affected versionversion=b878c8a7f08f0c225b6a46ba1ac867e9c5d17807 <9ad75e78747b5a50dc5a52f0f8e92e920a653f16
- Affected versionversion=fb265c9cb49e2074ddcdd4de99728aefdd3b3592 <0c0b4a49d3e7f49690a6827a41faeffad5df7e21
- Affected versionversion=fb265c9cb49e2074ddcdd4de99728aefdd3b3592 <681ff9a09accd8a4379f8bd30b7a1641ee19bb3e
- Affected versionversion=fb265c9cb49e2074ddcdd4de99728aefdd3b3592 <76dc776153a47372719d664e0fc50d6355791abb
- Affected versionversion=fb265c9cb49e2074ddcdd4de99728aefdd3b3592 <896a7e7d0d555ad8b2b46af0c2fa7de7467f9483
- Affected versionversion=fb265c9cb49e2074ddcdd4de99728aefdd3b3592 <a95df6f04f2c37291adf26a74205cde0314d4577
- Affected versionversion=fb265c9cb49e2074ddcdd4de99728aefdd3b3592 <b37c0edef4e66fb21a2fbc211471195a383e5ab8
- Affected versionversion=fb265c9cb49e2074ddcdd4de99728aefdd3b3592 <e941b712e758f615d311946bf98216e79145ccd9
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Published CVSS scores
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Attacks
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