CVE-2026-31535smb: client: make use of smbdirect_socket.recv_io.credits.available

Official description

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.

Affected packages & fixed versions

Affected products (as reported)

References

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