BUG/MEDIUM: h2: only destroy the h2s if h2s->cs is NULL.

In h2_deferred_shut(), only attempt to destroy the h2s if h2s->cs is NULL.
h2s->cs being non-NULL means it's still referenced by the stream interface,
so it may try to use it later, and that could lead to a crash.

This should be backported to 1.9.
1 file changed