Remove nsenter packages from vendor

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
(cherry picked from commit 0ff5026bbe)

vendor/golang.org/x/net/http2/hpack/encode.go

@@ -150,7 +150,7 @@ func appendIndexed(dst []byte, i uint64) []byte {
 // extended buffer.
 //
 // If f.Sensitive is true, "Never Indexed" representation is used. If
-// f.Sensitive is false and indexing is true, "Inremental Indexing"
+// f.Sensitive is false and indexing is true, "Incremental Indexing"
 // representation is used.
 func appendNewName(dst []byte, f HeaderField, indexing bool) []byte {
 	dst = append(dst, encodeTypeByte(indexing, f.Sensitive))

vendor/golang.org/x/net/http2/server.go

@@ -52,10 +52,11 @@ import (
 )
 
 const (
-	prefaceTimeout        = 10 * time.Second
-	firstSettingsTimeout  = 2 * time.Second // should be in-flight with preface anyway
-	handlerChunkWriteSize = 4 << 10
-	defaultMaxStreams     = 250 // TODO: make this 100 as the GFE seems to?
+	prefaceTimeout         = 10 * time.Second
+	firstSettingsTimeout   = 2 * time.Second // should be in-flight with preface anyway
+	handlerChunkWriteSize  = 4 << 10
+	defaultMaxStreams      = 250 // TODO: make this 100 as the GFE seems to?
+	maxQueuedControlFrames = 10000
 )
 
 var (
@@ -163,6 +164,15 @@ func (s *Server) maxConcurrentStreams() uint32 {
 	return defaultMaxStreams
 }
 
+// maxQueuedControlFrames is the maximum number of control frames like
+// SETTINGS, PING and RST_STREAM that will be queued for writing before
+// the connection is closed to prevent memory exhaustion attacks.
+func (s *Server) maxQueuedControlFrames() int {
+	// TODO: if anybody asks, add a Server field, and remember to define the
+	// behavior of negative values.
+	return maxQueuedControlFrames
+}
+
 type serverInternalState struct {
 	mu          sync.Mutex
 	activeConns map[*serverConn]struct{}
@@ -312,7 +322,7 @@ type ServeConnOpts struct {
 }
 
 func (o *ServeConnOpts) context() context.Context {
-	if o.Context != nil {
+	if o != nil && o.Context != nil {
 		return o.Context
 	}
 	return context.Background()
@@ -506,6 +516,7 @@ type serverConn struct {
 	sawFirstSettings            bool // got the initial SETTINGS frame after the preface
 	needToSendSettingsAck       bool
 	unackedSettings             int    // how many SETTINGS have we sent without ACKs?
+	queuedControlFrames         int    // control frames in the writeSched queue
 	clientMaxStreams            uint32 // SETTINGS_MAX_CONCURRENT_STREAMS from client (our PUSH_PROMISE limit)
 	advMaxStreams               uint32 // our SETTINGS_MAX_CONCURRENT_STREAMS advertised the client
 	curClientStreams            uint32 // number of open streams initiated by the client
@@ -894,6 +905,14 @@ func (sc *serverConn) serve() {
 			}
 		}
 
+		// If the peer is causing us to generate a lot of control frames,
+		// but not reading them from us, assume they are trying to make us
+		// run out of memory.
+		if sc.queuedControlFrames > sc.srv.maxQueuedControlFrames() {
+			sc.vlogf("http2: too many control frames in send queue, closing connection")
+			return
+		}
+
 		// Start the shutdown timer after sending a GOAWAY. When sending GOAWAY
 		// with no error code (graceful shutdown), don't start the timer until
 		// all open streams have been completed.
@@ -1093,6 +1112,14 @@ func (sc *serverConn) writeFrame(wr FrameWriteRequest) {
 	}
 
 	if !ignoreWrite {
+		if wr.isControl() {
+			sc.queuedControlFrames++
+			// For extra safety, detect wraparounds, which should not happen,
+			// and pull the plug.
+			if sc.queuedControlFrames < 0 {
+				sc.conn.Close()
+			}
+		}
 		sc.writeSched.Push(wr)
 	}
 	sc.scheduleFrameWrite()
@@ -1210,10 +1237,8 @@ func (sc *serverConn) wroteFrame(res frameWriteResult) {
 // If a frame is already being written, nothing happens. This will be called again
 // when the frame is done being written.
 //
-// If a frame isn't being written we need to send one, the best frame
-// to send is selected, preferring first things that aren't
-// stream-specific (e.g. ACKing settings), and then finding the
-// highest priority stream.
+// If a frame isn't being written and we need to send one, the best frame
+// to send is selected by writeSched.
 //
 // If a frame isn't being written and there's nothing else to send, we
 // flush the write buffer.
@@ -1241,6 +1266,9 @@ func (sc *serverConn) scheduleFrameWrite() {
 		}
 		if !sc.inGoAway || sc.goAwayCode == ErrCodeNo {
 			if wr, ok := sc.writeSched.Pop(); ok {
+				if wr.isControl() {
+					sc.queuedControlFrames--
+				}
 				sc.startFrameWrite(wr)
 				continue
 			}
@@ -1533,6 +1561,8 @@ func (sc *serverConn) processSettings(f *SettingsFrame) error {
 	if err := f.ForeachSetting(sc.processSetting); err != nil {
 		return err
 	}
+	// TODO: judging by RFC 7540, Section 6.5.3 each SETTINGS frame should be
+	// acknowledged individually, even if multiple are received before the ACK.
 	sc.needToSendSettingsAck = true
 	sc.scheduleFrameWrite()
 	return nil
@@ -2494,7 +2524,7 @@ const TrailerPrefix = "Trailer:"
 // trailers. That worked for a while, until we found the first major
 // user of Trailers in the wild: gRPC (using them only over http2),
 // and gRPC libraries permit setting trailers mid-stream without
-// predeclarnig them. So: change of plans. We still permit the old
+// predeclaring them. So: change of plans. We still permit the old
 // way, but we also permit this hack: if a Header() key begins with
 // "Trailer:", the suffix of that key is a Trailer. Because ':' is an
 // invalid token byte anyway, there is no ambiguity. (And it's already
@@ -2794,7 +2824,7 @@ func (sc *serverConn) startPush(msg *startPushRequest) {
 	// PUSH_PROMISE frames MUST only be sent on a peer-initiated stream that
 	// is in either the "open" or "half-closed (remote)" state.
 	if msg.parent.state != stateOpen && msg.parent.state != stateHalfClosedRemote {
-		// responseWriter.Push checks that the stream is peer-initiaed.
+		// responseWriter.Push checks that the stream is peer-initiated.
 		msg.done <- errStreamClosed
 		return
 	}

vendor/golang.org/x/net/http2/transport.go

@@ -1216,6 +1216,8 @@ var (
 
 	// abort request body write, but send stream reset of cancel.
 	errStopReqBodyWriteAndCancel = errors.New("http2: canceling request")
+
+	errReqBodyTooLong = errors.New("http2: request body larger than specified content length")
 )
 
 func (cs *clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (err error) {
@@ -1238,10 +1240,32 @@ func (cs *clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (
 
 	req := cs.req
 	hasTrailers := req.Trailer != nil
+	remainLen := actualContentLength(req)
+	hasContentLen := remainLen != -1
 
 	var sawEOF bool
 	for !sawEOF {
-		n, err := body.Read(buf)
+		n, err := body.Read(buf[:len(buf)-1])
+		if hasContentLen {
+			remainLen -= int64(n)
+			if remainLen == 0 && err == nil {
+				// The request body's Content-Length was predeclared and
+				// we just finished reading it all, but the underlying io.Reader
+				// returned the final chunk with a nil error (which is one of
+				// the two valid things a Reader can do at EOF). Because we'd prefer
+				// to send the END_STREAM bit early, double-check that we're actually
+				// at EOF. Subsequent reads should return (0, EOF) at this point.
+				// If either value is different, we return an error in one of two ways below.
+				var n1 int
+				n1, err = body.Read(buf[n:])
+				remainLen -= int64(n1)
+			}
+			if remainLen < 0 {
+				err = errReqBodyTooLong
+				cc.writeStreamReset(cs.ID, ErrCodeCancel, err)
+				return err
+			}
+		}
 		if err == io.EOF {
 			sawEOF = true
 			err = nil

vendor/golang.org/x/net/http2/writesched.go

@@ -32,7 +32,7 @@ type WriteScheduler interface {
 
 	// Pop dequeues the next frame to write. Returns false if no frames can
 	// be written. Frames with a given wr.StreamID() are Pop'd in the same
-	// order they are Push'd.
+	// order they are Push'd. No frames should be discarded except by CloseStream.
 	Pop() (wr FrameWriteRequest, ok bool)
 }
 
@@ -76,6 +76,12 @@ func (wr FrameWriteRequest) StreamID() uint32 {
 	return wr.stream.id
 }
 
+// isControl reports whether wr is a control frame for MaxQueuedControlFrames
+// purposes. That includes non-stream frames and RST_STREAM frames.
+func (wr FrameWriteRequest) isControl() bool {
+	return wr.stream == nil
+}
+
 // DataSize returns the number of flow control bytes that must be consumed
 // to write this entire frame. This is 0 for non-DATA frames.
 func (wr FrameWriteRequest) DataSize() int {

vendor/golang.org/x/net/http2/writesched_priority.go

@@ -149,7 +149,7 @@ func (n *priorityNode) addBytes(b int64) {
 }
 
 // walkReadyInOrder iterates over the tree in priority order, calling f for each node
-// with a non-empty write queue. When f returns true, this funcion returns true and the
+// with a non-empty write queue. When f returns true, this function returns true and the
 // walk halts. tmp is used as scratch space for sorting.
 //
 // f(n, openParent) takes two arguments: the node to visit, n, and a bool that is true