UdsStreamScheme::getsockopt held an outer socket_rc.borrow() across the
whole option match. The SO_PEERCRED branch calls get_connected_peer(id),
which itself does borrow_mut() on the same socket — a RefCell
double-borrow that panicked ipcd and took the UDS scheme down (observed
in QEMU boot logs as ipcd crash at uds/stream.rs plus tokio
UnixStream::pair / 'failed to create UnixStream' failures from clients
calling getsockopt(SO_PEERCRED)).
Borrow only inside the branches that read socket fields (SNDBUF/RCVBUF);
the SO_PEERCRED branch now runs without an outer borrow held.
(Change found as uncommitted work in the fork; committing to unblock the
clean-fork build gate and to preserve the fix.)
Red Bear OS
217935ec95