CVE-2026-31535 (GCVE-0-2026-31535)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:30 – Updated: 2026-05-11 22:10
VLAI
Title
smb: client: make use of smbdirect_socket.recv_io.credits.available
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: client: make use of smbdirect_socket.recv_io.credits.available The logic off managing recv credits by counting posted recv_io and granted credits is racy. That's because the peer might already consumed a credit, but between receiving the incoming recv at the hardware and processing the completion in the 'recv_done' functions we likely have a window where we grant credits, which don't really exist. So we better have a decicated counter for the available credits, which will be incremented when we posted new recv buffers and drained when we grant the credits to the peer.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 5fb9b459b3686e366640edd4e62805ef7b4de927 , < f664e6e8a81103cb45c8802a9bc7499e0902c458 (git)
Affected: 5fb9b459b3686e366640edd4e62805ef7b4de927 , < be8845ad5d6558703d20567d8702155598325db8 (git)
Affected: 5fb9b459b3686e366640edd4e62805ef7b4de927 , < 9911b1ed187a770a43950bf51f340ad4b7beecba (git)
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Linux Linux Affected: 6.18
Unaffected: 0 , < 6.18 (semver)
Unaffected: 6.18.11 , ≤ 6.18.* (semver)
Unaffected: 6.19.1 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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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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