src/go.mod                |  2 +-
 src/go.sum                |  4 ++--
 src/net/http/h2_bundle.go | 81 ++++++++++++++++++++++++++++++++---------------------
 src/vendor/modules.txt    |  2 +-

diff --git a/src/go.mod b/src/go.mod
index 25e7992a879fdbcbfe0492c853e265b17eb48491..1040d0506f4f6ea8edc49fb2382912d6d0ba69d6 100644
--- a/src/go.mod
+++ b/src/go.mod
@@ -4,7 +4,7 @@ go 1.16
 
 require (
 	golang.org/x/crypto v0.0.0-20201016220609-9e8e0b390897
-	golang.org/x/net v0.0.0-20211101194150-d8c3cde3c676
+	golang.org/x/net v0.0.0-20211201233224-64539c132272
 	golang.org/x/sys v0.0.0-20201204225414-ed752295db88 // indirect
 	golang.org/x/text v0.3.4 // indirect
 )
diff --git a/src/go.sum b/src/go.sum
index e5467ea1caca5efe1002ce4b5f0c0dba0e1f3cc4..6e22abb20a275826dea05a3128b7fa08ad31b347 100644
--- a/src/go.sum
+++ b/src/go.sum
@@ -2,8 +2,8 @@ golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20201016220609-9e8e0b390897 h1:pLI5jrR7OSLijeIDcmRxNmw2api+jEfxLoykJVice/E=
 golang.org/x/crypto v0.0.0-20201016220609-9e8e0b390897/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/net v0.0.0-20211101194150-d8c3cde3c676 h1:HdGRNh1uWfD+9WfeSGYgD64N7Nmu3oMnSkdZAONtoU8=
-golang.org/x/net v0.0.0-20211101194150-d8c3cde3c676/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/net v0.0.0-20211201233224-64539c132272 h1:yz7zX5EMX9IFSUDQtHpohPOP+fh7w1Me4FH/El1jctU=
+golang.org/x/net v0.0.0-20211201233224-64539c132272/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
diff --git a/src/net/http/h2_bundle.go b/src/net/http/h2_bundle.go
index 0fd8da1d15cf5720d2eea14f5e3845c77b17c9ac..735f1b5eac604bc854dc64043628047696b0b51b 100644
--- a/src/net/http/h2_bundle.go
+++ b/src/net/http/h2_bundle.go
@@ -7653,36 +7653,49 @@ 			return http2errRequestCanceled
 		}
 	}
 
+	handleResponseHeaders := func() (*Response, error) {
+		res := cs.res
+		if res.StatusCode > 299 {
+			// On error or status code 3xx, 4xx, 5xx, etc abort any
+			// ongoing write, assuming that the server doesn't care
+			// about our request body. If the server replied with 1xx or
+			// 2xx, however, then assume the server DOES potentially
+			// want our body (e.g. full-duplex streaming:
+			// golang.org/issue/13444). If it turns out the server
+			// doesn't, they'll RST_STREAM us soon enough. This is a
+			// heuristic to avoid adding knobs to Transport. Hopefully
+			// we can keep it.
+			cs.abortRequestBodyWrite()
+		}
+		res.Request = req
+		res.TLS = cc.tlsState
+		if res.Body == http2noBody && http2actualContentLength(req) == 0 {
+			// If there isn't a request or response body still being
+			// written, then wait for the stream to be closed before
+			// RoundTrip returns.
+			if err := waitDone(); err != nil {
+				return nil, err
+			}
+		}
+		return res, nil
+	}
+
 	for {
 		select {
 		case <-cs.respHeaderRecv:
-			res := cs.res
-			if res.StatusCode > 299 {
-				// On error or status code 3xx, 4xx, 5xx, etc abort any
-				// ongoing write, assuming that the server doesn't care
-				// about our request body. If the server replied with 1xx or
-				// 2xx, however, then assume the server DOES potentially
-				// want our body (e.g. full-duplex streaming:
-				// golang.org/issue/13444). If it turns out the server
-				// doesn't, they'll RST_STREAM us soon enough. This is a
-				// heuristic to avoid adding knobs to Transport. Hopefully
-				// we can keep it.
-				cs.abortRequestBodyWrite()
-			}
-			res.Request = req
-			res.TLS = cc.tlsState
-			if res.Body == http2noBody && http2actualContentLength(req) == 0 {
-				// If there isn't a request or response body still being
-				// written, then wait for the stream to be closed before
-				// RoundTrip returns.
-				if err := waitDone(); err != nil {
-					return nil, err
-				}
+			return handleResponseHeaders()
+		case <-cs.abort:
+			select {
+			case <-cs.respHeaderRecv:
+				// If both cs.respHeaderRecv and cs.abort are signaling,
+				// pick respHeaderRecv. The server probably wrote the
+				// response and immediately reset the stream.
+				// golang.org/issue/49645
+				return handleResponseHeaders()
+			default:
+				waitDone()
+				return nil, cs.abortErr
 			}
-			return res, nil
-		case <-cs.abort:
-			waitDone()
-			return nil, cs.abortErr
 		case <-ctx.Done():
 			err := ctx.Err()
 			cs.abortStream(err)
@@ -7742,6 +7755,9 @@ 		<-cc.reqHeaderMu
 		return err
 	}
 	cc.addStreamLocked(cs) // assigns stream ID
+	if http2isConnectionCloseRequest(req) {
+		cc.doNotReuse = true
+	}
 	cc.mu.Unlock()
 
 	// TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere?
@@ -7765,12 +7781,12 @@ 		cs.requestedGzip = true
 	}
 
 	continueTimeout := cc.t.expectContinueTimeout()
-	if continueTimeout != 0 &&
-		!httpguts.HeaderValuesContainsToken(
-			req.Header["Expect"],
-			"100-continue") {
-		continueTimeout = 0
-		cs.on100 = make(chan struct{}, 1)
+	if continueTimeout != 0 {
+		if !httpguts.HeaderValuesContainsToken(req.Header["Expect"], "100-continue") {
+			continueTimeout = 0
+		} else {
+			cs.on100 = make(chan struct{}, 1)
+		}
 	}
 
 	// Past this point (where we send request headers), it is possible for
@@ -7839,6 +7855,7 @@ 			return nil
 		case <-respHeaderTimer:
 			return http2errTimeout
 		case <-respHeaderRecv:
+			respHeaderRecv = nil
 			respHeaderTimer = nil // keep waiting for END_STREAM
 		case <-cs.abort:
 			return cs.abortErr
diff --git a/src/vendor/modules.txt b/src/vendor/modules.txt
index a3768fd5894b2c827a6a84a4349343bd2934c927..652d4d07d24571b7833e527d67bfc31e68b46e7f 100644
--- a/src/vendor/modules.txt
+++ b/src/vendor/modules.txt
@@ -8,7 +8,7 @@ golang.org/x/crypto/curve25519
 golang.org/x/crypto/hkdf
 golang.org/x/crypto/internal/subtle
 golang.org/x/crypto/poly1305
-# golang.org/x/net v0.0.0-20211101194150-d8c3cde3c676
+# golang.org/x/net v0.0.0-20211201233224-64539c132272
 ## explicit
 golang.org/x/net/dns/dnsmessage
 golang.org/x/net/http/httpguts