{"api_version":"1","generated_at":"2026-07-09T13:08:13+00:00","cve":"CVE-2026-31538","urls":{"html":"https://cve.report/CVE-2026-31538","api":"https://cve.report/api/cve/CVE-2026-31538.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-31538","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-31538"},"summary":{"title":"smb: server: make use of smbdirect_socket.recv_io.credits.available","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: server: make use of 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's because the peer might already consumed a credit,\nbut between receiving the incoming recv at the hardware\nand processing the completion in the 'recv_done' functions\nwe likely have a window where we grant credits, which\ndon't really exist.\n\nSo we better have a decicated counter for the\navailable credits, 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server: make use of smbdirect_socket.recv_io.credits.availa","CVE":"CVE-2026-31538","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"31538","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: server: make use of 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's because the peer might already consumed a credit,\nbut between receiving the incoming recv at the hardware\nand processing the completion in the 'recv_done' functions\nwe likely have a window where we grant credits, which\ndon't 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.\n\nThis fixes regression Namjae reported with\nthe 6.18 release.","Type":"Description","Title":"smb: server: make use of smbdirect_socket.recv_io.credits.availa"}]}}}