Fixed buffer overread with unix sockets after accept(). Some OSes (notably macOS, NetBSD, and Solaris) allow unix socket addresses larger than struct sockaddr_un. Moreover, some of them (macOS, Solaris) return socklen of the socket address before it was truncated to fit the buffer provided. As such, on these systems socklen must not be used without additional check that it is within the buffer provided. Appropriate checks added to ngx_event_accept() (after accept()), ngx_event_recvmsg() (after recvmsg()), and ngx_set_inherited_sockets() (after getsockname()). We also obtain socket addresses via getsockname() in ngx_connection_local_sockaddr(), but it does not need any checks as it is only used for INET and INET6 sockets (as there can be no wildcard unix sockets).

scgi_param  REQUEST_METHOD     $request_method;
scgi_param  REQUEST_URI        $request_uri;
scgi_param  QUERY_STRING       $query_string;
scgi_param  CONTENT_TYPE       $content_type;

scgi_param  DOCUMENT_URI       $document_uri;
scgi_param  DOCUMENT_ROOT      $document_root;
scgi_param  SCGI               1;
scgi_param  SERVER_PROTOCOL    $server_protocol;
scgi_param  REQUEST_SCHEME     $scheme;
scgi_param  HTTPS              $https if_not_empty;

scgi_param  REMOTE_ADDR        $remote_addr;
scgi_param  REMOTE_PORT        $remote_port;
scgi_param  SERVER_PORT        $server_port;
scgi_param  SERVER_NAME        $server_name;