From 343702bf616b21729930379c79d7caf8878751bd Mon Sep 17 00:00:00 2001 From: Craig Tiller Date: Thu, 9 Mar 2017 10:25:04 -0800 Subject: Write an essay --- src/core/ext/transport/chttp2/transport/parsing.c | 42 +++++++++++++++++------ 1 file changed, 32 insertions(+), 10 deletions(-) diff --git a/src/core/ext/transport/chttp2/transport/parsing.c b/src/core/ext/transport/chttp2/transport/parsing.c index 7ed00522c3..e7f2597f89 100644 --- a/src/core/ext/transport/chttp2/transport/parsing.c +++ b/src/core/ext/transport/chttp2/transport/parsing.c @@ -381,16 +381,38 @@ static grpc_error *update_incoming_window(grpc_exec_ctx *exec_ctx, s->incoming_window_delta + t->settings[GRPC_ACKED_SETTINGS] [GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]) { - char *msg; - gpr_asprintf(&msg, - "frame of size %d overflows incoming window of %" PRId64, - t->incoming_frame_size, - s->incoming_window_delta + - t->settings[GRPC_ACKED_SETTINGS] - [GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]); - grpc_error *err = GRPC_ERROR_CREATE(msg); - gpr_free(msg); - return err; + if (incoming_frame_size <= + s->incoming_window_delta + + t->settings[GRPC_SENT_SETTINGS] + [GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]) { + gpr_log( + GPR_ERROR, + "Incoming frame of size %d exceeds incoming window size of %" PRId64 + ".\n" + "The (un-acked, future) window size would be %" PRId64 + " which is not exceeded.\n" + "This would usually cause a disconnection, but allowing it due to " + "broken HTTP2 implementations in the wild.\n" + "See (for example) https://github.com/netty/netty/issues/6520.", + t->incoming_frame_size, + s->incoming_window_delta + + t->settings[GRPC_ACKED_SETTINGS] + [GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE], + s->incoming_window_delta + + t->settings[GRPC_SENT_SETTINGS] + [GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]); + } else { + char *msg; + gpr_asprintf(&msg, + "frame of size %d overflows incoming window of %" PRId64, + t->incoming_frame_size, + s->incoming_window_delta + + t->settings[GRPC_ACKED_SETTINGS] + [GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]); + grpc_error *err = GRPC_ERROR_CREATE(msg); + gpr_free(msg); + return err; + } } GRPC_CHTTP2_FLOW_DEBIT_STREAM_INCOMING_WINDOW_DELTA("parse", t, s, -- cgit v1.2.3