Fix use after free, other.bev may be NULL

pxyconn.c

@@ -3042,9 +3042,9 @@ pxy_bev_eventcb(struct bufferevent *bev, short events, void *arg)
 									bufferevent_get_input(bev)),
 								evbuffer_get_length(
 									bufferevent_get_output(bev)),
-								evbuffer_get_length(
+								other->closed ? 0 : evbuffer_get_length(
 									bufferevent_get_input(other->bev)),
-								evbuffer_get_length(
+								other->closed ? 0 : evbuffer_get_length(
 									bufferevent_get_output(other->bev))
 								);
 			}