diff --git a/dix/events.c b/dix/events.c
index 3e3a01ef9..d3a33ea3f 100644
--- a/dix/events.c
+++ b/dix/events.c
@@ -5366,6 +5366,12 @@ ProcSendEvent(ClientPtr client)
         client->errorValue = stuff->event.u.u.type;
         return BadValue;
     }
+    /* Generic events can have variable size, but SendEvent request holds
+       exactly 32B of event data. */
+    if (stuff->event.u.u.type == GenericEvent) {
+        client->errorValue = stuff->event.u.u.type;
+        return BadValue;
+    }
     if (stuff->event.u.u.type == ClientMessage &&
         stuff->event.u.u.detail != 8 &&
         stuff->event.u.u.detail != 16 && stuff->event.u.u.detail != 32) {
diff --git a/dix/swapreq.c b/dix/swapreq.c
index 719e9b81c..67850593b 100644
--- a/dix/swapreq.c
+++ b/dix/swapreq.c
@@ -292,6 +292,13 @@ SProcSendEvent(ClientPtr client)
     swapl(&stuff->destination);
     swapl(&stuff->eventMask);
 
+    /* Generic events can have variable size, but SendEvent request holds
+       exactly 32B of event data. */
+    if (stuff->event.u.u.type == GenericEvent) {
+        client->errorValue = stuff->event.u.u.type;
+        return BadValue;
+    }
+
     /* Swap event */
     proc = EventSwapVector[stuff->event.u.u.type & 0177];
     if (!proc || proc == NotImplemented)        /* no swapping proc; invalid event type? */