add ImageData protections

Author: annevk

source

@@ -8283,9 +8283,9 @@ interface <dfn>DOMStringList</dfn> {
         <p>If <var>agentCluster</var>'s <span>allow sidechannel attacks</span> is set to false, then
         throw a <span>"<code>DataCloneError</code>"</span> <code>DOMException</code>.</p>
 
-        <p class="note">This check is only needed once as <span>allow sidechannel attacks</span>
-        cannot change over time and a <code>SharedArrayBuffer</code> cannot leave an <span>agent
-        cluster</span>.</p>
+        <p class="note">This check is only needed when serializing (and not when deserializing) as
+        <span>allow sidechannel attacks</span> cannot change over time and a
+        <code>SharedArrayBuffer</code> cannot leave an <span>agent cluster</span>.</p>
        </li>
 
        <li><p>If <var>forStorage</var> is true, then throw a
@@ -95267,6 +95267,17 @@ dictionary <dfn>ImageBitmapOptions</dfn> {
   are:</p>
 
   <ol>
+   <li>
+    <p>If <var>serialized</var>.[[OriginClean]] is false and <span>surrounding agent</span>'s
+    <span>agent cluster</span>'s <span>allow sidechannel attacks</span> is true, then throw a
+    <span>"<code>DataCloneError</code>"</span> <code>DOMException</code>.</p>
+
+    <p class="warning">To protect against sidechannel attacks implementations should avoid
+    transmitting <var>serialized</var>.[[BitmapData]], when <var>serialized</var>.[[OriginClean]] is
+    false, to <span data-x="agent cluster">agent clusters</span> whose <span>allow sidechannel
+    attacks</span> is true.</p>
+   </li>
+
    <li><p>Set <var>value</var>'s <span data-x="concept-ImageBitmap-bitmap-data">bitmap data</span>
    to <var>serialized</var>.[[BitmapData]].</p></li>
 
@@ -95292,6 +95303,17 @@ dictionary <dfn>ImageBitmapOptions</dfn> {
   are:</p>
 
   <ol>
+   <li>
+    <p>If <var>dataHolder</var>.[[OriginClean]] is false and <span>surrounding agent</span>'s
+    <span>agent cluster</span>'s <span>allow sidechannel attacks</span> is true, then throw a
+    <span>"<code>DataCloneError</code>"</span> <code>DOMException</code>.</p>
+
+    <p class="warning">To protect against sidechannel attacks implementations should avoid sharing
+    <var>dataHolder</var>.[[BitmapData]], when <var>dataHolder</var>.[[OriginClean]] is false, with
+    <span data-x="agent cluster">agent clusters</span> whose <span>allow sidechannel attacks</span>
+    is true.</p>
+   </li>
+
    <li><p>Set <var>value</var>'s <span data-x="concept-ImageBitmap-bitmap-data">bitmap data</span>
    to <var>dataHolder</var>.[[BitmapData]].</p></li>