Local udmabuf creation failure via oversized allocation
Published Dec 27, 2024 · Updated May 11, 2026
NULL pointer dereference in Linux 4.20 and later affected releases allows local users to interrupt udmabuf creation via a large buffer request. udmabuf_create uses kmalloc_array for its folio-pointer array, which cannot satisfy oversized or fragmented contiguous allocations and returns NULL. Reachability requires local access to the udmabuf interface; a sufficiently large request produces a kernel warning and failed buffer creation, with no reported data disclosure or modification.
Summary
What happened
NULL pointer dereference in Linux 4.20 and later affected releases allows local users to interrupt udmabuf creation via a large buffer request. udmabuf_create uses kmalloc_array for its folio-pointer array, which cannot satisfy oversized or fragmented contiguous allocations and returns NULL. Reachability requires local access to the udmabuf interface; a sufficiently large request produces a kernel warning and failed buffer creation, with no reported data disclosure or modification.
The record
- CVE
- CVE-2024-56544
- Published
- Dec 27, 2024
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-476, T1499.001
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 27, 2024CVE 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=4.20
- Affected versionversion=fbb0de795078190a9834b3409e4b009cfb18a6d4 <1c0844c6184e658064e14c4335885785ad3bf84b
- Affected versionversion=fbb0de795078190a9834b3409e4b009cfb18a6d4 <2acc6192aa8570661ed37868c02c03002b1dc290
- Affected versionversion=fbb0de795078190a9834b3409e4b009cfb18a6d4 <85bb72397cb63649fe493c96e27e1d0e4ed2ff63
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What is affected?
Published CVSS scores
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Attacks
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