http2: prioritize RST_STREAM frames in random write scheduler
The http2 random write scheduler should not queue RST_STREAM
frames with the DATA frames, and instead treat them as control frames.
There can be deadlock situations if data frames block the queue,
because if the sender wants to close the stream it sends an RST frame,
but if the client is not draining the queue, the RST frame is stuck
and the sender is not able to finish.
Fixes golang/go#49741
Change-Id: I0940a76d1aad95f1c4d3856e4d79cf5ce2a78ff2
Reviewed-on: https://go-review.googlesource.com/c/net/+/367154
Trust: Dave Cheney <dave@cheney.net>
Reviewed-by: Damien Neil <dneil@google.com>
Trust: Damien Neil <dneil@google.com>
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
diff --git a/http2/writesched_random.go b/http2/writesched_random.go
index 9a7b9e5..f2e55e0 100644
--- a/http2/writesched_random.go
+++ b/http2/writesched_random.go
@@ -45,11 +45,11 @@
}
func (ws *randomWriteScheduler) Push(wr FrameWriteRequest) {
- id := wr.StreamID()
- if id == 0 {
+ if wr.isControl() {
ws.zero.push(wr)
return
}
+ id := wr.StreamID()
q, ok := ws.sq[id]
if !ok {
q = ws.queuePool.get()
@@ -59,7 +59,7 @@
}
func (ws *randomWriteScheduler) Pop() (FrameWriteRequest, bool) {
- // Control frames first.
+ // Control and RST_STREAM frames first.
if !ws.zero.empty() {
return ws.zero.shift(), true
}
