CVE-2026-31535

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.

Thats 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 dont 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.

Weakness

The product checks the state of a resource before using that resource, but the resource’s state can change between the check and the use in a way that invalidates the results of the check.

Affected Software

Potential Mitigations

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/27.html
• https://cwe.mitre.org/data/definitions/29.html

References

• https://git.kernel.org/stable/c/9911b1ed187a770a43950bf51f340ad4b7beecba
• https://git.kernel.org/stable/c/be8845ad5d6558703d20567d8702155598325db8
• https://git.kernel.org/stable/c/f664e6e8a81103cb45c8802a9bc7499e0902c458