tree 316721ea635289c05f938107f06238bc96f0e69d
parent 74ec9fe8713c04397c63e26d9d29392d62cbb39a
author Roman Arutyunyan <arut@nginx.com> 1547487383 +0300
committer Roman Arutyunyan <arut@nginx.com> 1547487383 +0300

Prevented scheduling events on a shared connection.

A shared connection does not own its file descriptor, which means that
ngx_handle_read_event/ngx_handle_write_event calls should do nothing for it.
Currently the c->shared flag is checked in several places in the stream proxy
module prior to calling these functions.  However it was not done everywhere.
Missing checks could lead to calling
ngx_handle_read_event/ngx_handle_write_event on shared connections.

The problem manifested itself when using proxy_upload_rate and resulted in
either duplicate file descriptor error (e.g. with epoll) or incorrect further
udp packet processing (e.g. with kqueue).

The fix is to set and reset the event active flag in a way that prevents
ngx_handle_read_event/ngx_handle_write_event from scheduling socket events.