CVE-2026-46256 (GCVE-0-2026-46256)

Vulnerability from cvelistv5 – Published: 2026-06-03 15:49 – Updated: 2026-06-03 15:49
VLAI
Title
NFS/localio: prevent direct reclaim recursion into NFS via nfs_writepages
Summary
In the Linux kernel, the following vulnerability has been resolved: NFS/localio: prevent direct reclaim recursion into NFS via nfs_writepages LOCALIO is an NFS loopback mount optimization that avoids using the network for READ, WRITE and COMMIT if the NFS client and server are determined to be on the same system. But because LOCALIO is still fundamentally "just NFS loopback mount" it is susceptible to recursion deadlock via direct reclaim, e.g.: NFS LOCALIO down to XFS and then back into NFS via nfs_writepages. Fix LOCALIO's potential for direct reclaim deadlock by ensuring that all its page cache allocations are done from GFP_NOFS context. Thanks to Ben Coddington for pointing out commit ad22c7a043c2 ("xfs: prevent stack overflows from page cache allocation").
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 70ba381e1a431245c137ed597ec6a05991c79bd9 , < ae26a4cf2baf0a44c538dc093504d1994b02dade (git)
Affected: 70ba381e1a431245c137ed597ec6a05991c79bd9 , < 6a5de0c4fc0f217eea945d3d72c34ee30d72cbc9 (git)
Affected: 70ba381e1a431245c137ed597ec6a05991c79bd9 , < 67435d2d8a33a75f9647724952cb1b18279d2e95 (git)
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Linux Linux Affected: 6.12
Unaffected: 0 , < 6.12 (semver)
Unaffected: 6.18.14 , ≤ 6.18.* (semver)
Unaffected: 6.19.4 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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      "title": "kernel: NFS/localio: prevent direct reclaim recursion into NFS via nfs_writepages",
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      "id": "CVE-2026-46256",
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      "title": "SUSE CVE CVE-2026-46256",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • 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.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • 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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