CVE-2026-31539 (GCVE-0-2026-31539)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:30 – Updated: 2026-08-05 12:23
VLAI
Title
smb: smbdirect: introduce smbdirect_socket.recv_io.credits.available
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: smbdirect: introduce 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
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 5fb9b459b3686e366640edd4e62805ef7b4de927 , < e811e60e1cc79923c4388146eb1fa26a7482731e (git)
Affected: 5fb9b459b3686e366640edd4e62805ef7b4de927 , < f99996870222b598914a1f49d7375dc23752c237 (git)
Affected: 5fb9b459b3686e366640edd4e62805ef7b4de927 , < 6e3c5052f9686192e178806e017b7377155f4bab (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)
guessed Create a notification for this product.
Show details on NVD website
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            "fs/smb/common/smbdirect/smbdirect_socket.h"
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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.

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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.
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  • 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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