vsock: prevent null-ptr-deref in vsock_*[has_data|has_space]

These records connect through source-stated identifiers. Shared identifiers or dates alone do not establish shared exposure, root cause or applicability.

CVE-2025-21666 · Microsoft / collected KEV context

cve-program · CVE-2025-21666

• https://git.kernel.org/stable/c/daeac89cdb03d30028186f5ff7dc26ec8fa843e7
• https://git.kernel.org/stable/c/9e5fed46ccd2c34c5fa5a9c8825ce4823fdc853e
• https://git.kernel.org/stable/c/b52e50dd4fabd12944172bd486a4f4853b7f74dd
• https://git.kernel.org/stable/c/bc9c49341f9728c31fe248c5fbba32d2e81a092b
• https://git.kernel.org/stable/c/c23d1d4f8efefb72258e9cedce29de10d057f8ca
• https://git.kernel.org/stable/c/91751e248256efc111e52e15115840c35d85abaf

No related operational record is retained in the current change model.