The connection_ap_attach_pending() function processes all pending
streams in the pending_entry_connections list. It first copy the pointer
and then allocates a brand new empty list.
It then iterates over that copy pointer to try to attach entry
connections onto any fitting circuits using
connection_ap_handshake_attach_circuit().
That very function, for onion service, can lead to flagging _all_
streams of the same onion service to be put in state RENDDESC_WAIT from
CIRCUIT_WAIT. By doing so, it also tries to remove them from the
pending_entry_connections but at that point it is already empty.
Problem is that the we are iterating over the previous
pending_entry_connections which contains the streams that have just
changed state and are no longer in CIRCUIT_WAIT.
This lead to this bug warning occuring a lot on busy services:
May 01 08:55:43.000 [warn] connection_ap_attach_pending(): Bug:
0x55d8764ae550 is no longer in circuit_wait. Its current state is
waiting for rendezvous desc. Why is it on pending_entry_connections?
(on Tor 0.4.4.0-alpha-dev )
This fix is minimal and basically allow a state to be not CIRCUIT_WAIT
and move on to the next one without logging a warning. Because the
pending_entry_connections is emptied before processing, there is no
chance for a streams to be stuck there forever thus it is OK to ignore
streams not in the right state.
Fixes#34083
Signed-off-by: David Goulet <dgoulet@torproject.org>
