CVE-2026-31438 (GCVE-0-2026-31438)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:53 – Updated: 2026-04-22 13:53
VLAI?
Title
netfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators
Summary
In the Linux kernel, the following vulnerability has been resolved: netfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators When a process crashes and the kernel writes a core dump to a 9P filesystem, __kernel_write() creates an ITER_KVEC iterator. This iterator reaches netfs_limit_iter() via netfs_unbuffered_write(), which only handles ITER_FOLIOQ, ITER_BVEC and ITER_XARRAY iterator types, hitting the BUG() for any other type. Fix this by adding netfs_limit_kvec() following the same pattern as netfs_limit_bvec(), since both kvec and bvec are simple segment arrays with pointer and length fields. Dispatch it from netfs_limit_iter() when the iterator type is ITER_KVEC.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: cae932d3aee55035a54415dcea8e7ecf2ec469b5 , < 18c2e20b42dd21db599e42d05ddaeeb647b2bb6d (git)
Affected: cae932d3aee55035a54415dcea8e7ecf2ec469b5 , < 4bc2d72c7695cedf6d4e1a558924903c2b28a78e (git)
Affected: cae932d3aee55035a54415dcea8e7ecf2ec469b5 , < 00d6df7115f6972370974212de9088087820802e (git)
Affected: cae932d3aee55035a54415dcea8e7ecf2ec469b5 , < 67e467a11f62ff64ad219dc6aa5459e132c79d14 (git)
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    Linux Linux Affected: 6.8
Unaffected: 0 , < 6.8 (semver)
Unaffected: 6.12.80 , ≤ 6.12.* (semver)
Unaffected: 6.18.21 , ≤ 6.18.* (semver)
Unaffected: 6.19.11 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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