--- a/js/src/shell/js.cpp
+++ b/js/src/shell/js.cpp
@@ -5805,23 +5805,16 @@ EnsureLatin1CharsLinearString(JSContext*
     result.set(&str->asLinear());
     MOZ_ASSERT(result->hasLatin1Chars());
     return true;
 }
 
 static bool
 ConsumeBufferSource(JSContext* cx, JS::HandleObject obj, JS::MimeType, JS::StreamConsumer* consumer)
 {
-    SharedMem<uint8_t*> dataPointer;
-    size_t byteLength;
-    if (!IsBufferSource(obj, &dataPointer, &byteLength)) {
-        JS_ReportErrorASCII(cx, "shell streaming consumes a buffer source (buffer or view)");
-        return false;
-    }
-
     {
         RootedValue url(cx);
         if (!JS_GetProperty(cx, obj, "url", &url))
             return false;
         RootedLinearString urlStr(cx);
         if (!EnsureLatin1CharsLinearString(cx, url, &urlStr))
             return false;
 
@@ -5836,16 +5829,23 @@ ConsumeBufferSource(JSContext* cx, JS::H
         consumer->noteResponseURLs(urlStr
                                    ? reinterpret_cast<const char*>(urlStr->latin1Chars(nogc))
                                    : nullptr,
                                    mapUrlStr
                                    ? reinterpret_cast<const char*>(mapUrlStr->latin1Chars(nogc))
                                    : nullptr);
     }
 
+    SharedMem<uint8_t*> dataPointer;
+    size_t byteLength;
+    if (!IsBufferSource(obj, &dataPointer, &byteLength)) {
+        JS_ReportErrorASCII(cx, "shell streaming consumes a buffer source (buffer or view)");
+        return false;
+    }
+
     auto job = cx->make_unique<BufferStreamJob>(consumer);
     if (!job || !job->bytes.resize(byteLength))
         return false;
 
     memcpy(job->bytes.begin(), dataPointer.unwrap(), byteLength);
 
     BufferStreamJob* jobPtr = job.get();
 

--- a/js/src/vm/TypedArrayObject.cpp
+++ b/js/src/vm/TypedArrayObject.cpp
@@ -2135,16 +2135,17 @@ js::IsBufferSource(JSObject* object, Sha
         *byteLength = view.byteLength();
         return true;
     }
 
     if (object->is<DataViewObject>()) {
         DataViewObject& view = object->as<DataViewObject>();
         *dataPointer = view.dataPointerEither().cast<uint8_t*>();
         *byteLength = view.byteLength();
+        return true;
     }
 
     if (object->is<ArrayBufferObject>()) {
         ArrayBufferObject& buffer = object->as<ArrayBufferObject>();
         *dataPointer = buffer.dataPointerShared();
         *byteLength = buffer.byteLength();
         return true;
     }