fix(network): bound gethostname copy to guest namelen - #40
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trap_put_string() writes through the terminating NUL and ignores its maxlen on the direct-memory path, so a hostname longer than the caller's buffer spilled past the validated namelen range into adjacent guest memory. Truncate to namelen-1 plus NUL and copy with the strictly bounded trap_put_bytes().
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Follow-up to #39 (found by Codex post-merge):
host_gethostname()passed the guest-suppliednamelentotrap_put_string(), whose direct-memory path copies through the terminating NUL and ignoresmaxlen. A hostname longer than the caller's buffer wrote past thetrap_valid_address(name, namelen)range into adjacent guest memory.Fix: truncate the hostname to
namelen - 1characters, NUL-terminate, and copy withtrap_put_bytes(), which is strictly bounded by its byte count.namelen == 0now fails fast.Noted while auditing other
trap_put_string()callsites:cfgfile.cpp:8240andcfgfile.cpp:8282have the same guest-length + host-string pattern (WinUAE-lineage code, predates #39) — proposing as a separate follow-up.Verification
socket_emu=true: no errors, clean exit