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

Vulnerability from cvelistv5 – Published: 2026-04-24 14:30 – Updated: 2026-04-24 14:30
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 ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
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)
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: smbdirect: introduce smbdirect_socket.recv_io.credits.available\n\nThe logic off managing recv credits by counting posted recv_io and\ngranted credits is racy.\n\nThat\u0027s because the peer might already consumed a credit,\nbut between receiving the incoming recv at the hardware\nand processing the completion in the \u0027recv_done\u0027 functions\nwe likely have a window where we grant credits, which\ndon\u0027t really exist.\n\nSo we better have a decicated counter for the\navailable credits, which will be incremented\nwhen we posted new recv buffers and drained when\nwe grant the credits to the peer."
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        "dateUpdated": "2026-04-24T14:30:26.326Z",
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    "dateReserved": "2026-03-09T15:48:24.114Z",
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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