2 files changed, 12 insertions, 1 deletions

diff --git a/ui/vnc.c b/ui/vnc.c
index c302bb0..acb5646 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -2195,7 +2195,10 @@ static void set_encodings(VncState *vs, int32_t *encodings, size_t n_encodings)
             send_ext_key_event_ack(vs);
             break;
         case VNC_ENCODING_AUDIO:
-            send_ext_audio_ack(vs);
+            if (vs->vd->audio_state) {
+                vs->features |= VNC_FEATURE_AUDIO_MASK;
+                send_ext_audio_ack(vs);
+            }
             break;
         case VNC_ENCODING_WMVi:
             vs->features |= VNC_FEATURE_WMVI_MASK;
@@ -2502,6 +2505,12 @@ static int protocol_client_msg(VncState *vs, uint8_t *data, size_t len)
                           read_u32(data, 4), read_u32(data, 8));
             break;
         case VNC_MSG_CLIENT_QEMU_AUDIO:
+            if (!vnc_has_feature(vs, VNC_FEATURE_AUDIO)) {
+                error_report("Audio message %d with audio disabled", read_u8(data, 2));
+                vnc_client_error(vs);
+                break;
+            }
+
             if (len == 2)
                 return 4;
 
diff --git a/ui/vnc.h b/ui/vnc.h
index 757fa83..96d19dc 100644
--- a/ui/vnc.h
+++ b/ui/vnc.h
@@ -464,6 +464,7 @@ enum VncFeatures {
     VNC_FEATURE_LED_STATE,
     VNC_FEATURE_XVP,
     VNC_FEATURE_CLIPBOARD_EXT,
+    VNC_FEATURE_AUDIO,
 };
 
 #define VNC_FEATURE_RESIZE_MASK              (1 << VNC_FEATURE_RESIZE)
@@ -481,6 +482,7 @@ enum VncFeatures {
 #define VNC_FEATURE_LED_STATE_MASK           (1 << VNC_FEATURE_LED_STATE)
 #define VNC_FEATURE_XVP_MASK                 (1 << VNC_FEATURE_XVP)
 #define VNC_FEATURE_CLIPBOARD_EXT_MASK       (1 <<  VNC_FEATURE_CLIPBOARD_EXT)
+#define VNC_FEATURE_AUDIO_MASK               (1 <<  VNC_FEATURE_AUDIO)
 
 
 /* Client -> Server message IDs */