When a content receiver returned false, or threw, partway through a body,
the drain after the response read a whole Content-Length again from where
it stopped. It swallowed the start of the next request, so the rest was
parsed as a request of its own once the handler answered below 400. A
handler that called the content reader a second time read into the next
request the same way.
Mark the body once reading starts, and if it does not finish, answer with
Connection: close and never drain it from the middle. Let each request's
body be read only once.
yhirose
fc0e8230ba
