Collect auth requirements for bidirectional source peers and fix follow-up review findings

client/cmd/vnc_agent.go

@@ -21,7 +21,7 @@ var (
 
 func init() {
 	vncAgentCmd.Flags().StringVar(&vncAgentSocket, "socket", "", "Unix-domain socket path the agent listens on (required)")
-	vncAgentCmd.Flags().Uint32Var(&vncAgentTargetUID, "target-uid", 0, "uid the agent should drop privileges to before listening (darwin only; 0 = stay as current uid)")
+	vncAgentCmd.Flags().Uint32Var(&vncAgentTargetUID, "target-uid", 0, "uid the agent drops privileges to before listening (darwin only; required there, and must not be 0)")
 	rootCmd.AddCommand(vncAgentCmd)
 }
 

client/vnc/server/cursor_x11.go

@@ -69,13 +69,16 @@ func (c *xfixesCursor) Cursor() (*image.RGBA, int, int, uint64, error) {
 		return nil, 0, 0, 0, fmt.Errorf("cursor has zero extent")
 	}
 	// Anything past maxCursorDim is discarded by the encoder, so decoding it
-	// would allocate and convert a sprite that can only be thrown away. Keep
-	// showing the last good cursor instead.
+	// would allocate and convert a sprite that can only be thrown away. Report
+	// it as "nothing new" rather than an error: the caller latches a cursor
+	// error for the rest of the session, and an oversized sprite is a property
+	// of the current cursor, not of the source. The next ordinary cursor is
+	// still delivered.
 	if w > maxCursorDim || h > maxCursorDim {
 		if c.lastImg != nil {
 			return c.lastImg, c.lastHotX, c.lastHotY, c.lastSerial, nil
 		}
-		return nil, 0, 0, 0, fmt.Errorf("cursor %dx%d exceeds %d", w, h, maxCursorDim)
+		return nil, 0, 0, 0, nil
 	}
 	if len(reply.CursorImage) < w*h {
 		if c.lastImg != nil {

client/vnc/server/input_x11.go

@@ -273,15 +273,15 @@ func (x *X11InputInjector) TypeText(text string) {
 		if !ok {
 			continue
 		}
-		x.typeRuneLocked(keysym, shift)
+		x.typeRune(keysym, shift)
 	}
 }
 
-// typeRuneLocked emits one rune, framed by Shift-down/up when the keysym needs
-// it. Locked per rune rather than for the whole string: the framing has to be
-// atomic, but a long paste must not hold another session's pointer off for the
-// length of it.
-func (x *X11InputInjector) typeRuneLocked(keysym uint32, shift bool) {
+// typeRune emits one rune, framed by Shift-down/up when the keysym needs it. It
+// takes inputMu itself, per rune rather than for the whole string: the framing
+// has to be atomic, but a long paste must not hold another session's pointer
+// off for the length of it.
+func (x *X11InputInjector) typeRune(keysym uint32, shift bool) {
 	x.inputMu.Lock()
 	defer x.inputMu.Unlock()