>>
> What path does this occur in? __sctp_lookup_association takes a hold on the
> asoc, and that function is protected by the rcu_read_lock, so I'm not sure how
> you get into a situation in which the asoc can be deleted while the lookup is
> occuring.
>
yes that function is protected by the rcu_read_lock, it can only
ensure sctp_transport_destroy_rcu will NOT be called. But,
sctp_transport_destroy can be called by sctp_assocation_free.
in which, sctp free and unhash all the transport. when transport's
defcnt become 0, sctp will call sctp_transport_destroy, in which,
asoc can be destroyed because of:
if (transport->asoc)
sctp_association_put(transport->asoc);
