--- a/gfx/2d/DrawTargetCairo.cpp
+++ b/gfx/2d/DrawTargetCairo.cpp
@@ -1475,18 +1475,19 @@ TemporaryRef<DrawTarget>
 DrawTargetCairo::CreateSimilarDrawTarget(const IntSize &aSize, SurfaceFormat aFormat) const
 {
   cairo_surface_t* similar = cairo_surface_create_similar(mSurface,
                                                           GfxFormatToCairoContent(aFormat),
                                                           aSize.width, aSize.height);
 
   if (!cairo_surface_status(similar)) {
     RefPtr<DrawTargetCairo> target = new DrawTargetCairo();
-    target->InitAlreadyReferenced(similar, aSize);
-    return target.forget();
+    if (target->InitAlreadyReferenced(similar, aSize)) {
+      return target.forget();
+    }
   }
 
   gfxCriticalError() << "Failed to create similar cairo surface! Size: " << aSize << " Status: " << cairo_surface_status(similar);
 
   return nullptr;
 }
 
 bool
@@ -1532,18 +1533,21 @@ DrawTargetCairo::CreateShadowDrawTarget(
   if (cairo_surface_status(similar)) {
     return nullptr;
   }
 
   // If we don't have a blur then we can use the RGBA mask and keep all the
   // operations in graphics memory.
   if (aSigma == 0.0F) {
     RefPtr<DrawTargetCairo> target = new DrawTargetCairo();
-    target->InitAlreadyReferenced(similar, aSize);
-    return target.forget();
+    if (target->InitAlreadyReferenced(similar, aSize)) {
+      return target.forget();
+    } else {
+      return nullptr;
+    }
   }
 
   cairo_surface_t* blursurf = cairo_image_surface_create(CAIRO_FORMAT_A8,
                                                          aSize.width,
                                                          aSize.height);
 
   if (cairo_surface_status(blursurf)) {
     return nullptr;
@@ -1555,18 +1559,20 @@ DrawTargetCairo::CreateShadowDrawTarget(
     cairo_surface_destroy(similar);
     return nullptr;
   }
 
   cairo_tee_surface_add(tee, similar);
   cairo_surface_destroy(similar);
 
   RefPtr<DrawTargetCairo> target = new DrawTargetCairo();
-  target->InitAlreadyReferenced(tee, aSize);
-  return target.forget();
+  if (target->InitAlreadyReferenced(tee, aSize)) {
+    return target.forget();
+  }
+  return nullptr;
 }
 
 bool
 DrawTargetCairo::Init(cairo_surface_t* aSurface, const IntSize& aSize, SurfaceFormat* aFormat)
 {
   cairo_surface_reference(aSurface);
   return InitAlreadyReferenced(aSurface, aSize, aFormat);
 }

--- a/gfx/layers/client/TextureClient.cpp
+++ b/gfx/layers/client/TextureClient.cpp
@@ -706,17 +706,17 @@ BufferTextureClient::GetAllocator() cons
   return mAllocator;
 }
 
 bool
 BufferTextureClient::AllocateForSurface(gfx::IntSize aSize, TextureAllocationFlags aFlags)
 {
   MOZ_ASSERT(IsValid());
   MOZ_ASSERT(mFormat != gfx::SurfaceFormat::YUV, "This textureClient cannot use YCbCr data");
-  MOZ_ASSERT(aSize.width * aSize.height);
+  MOZ_ASSERT(aSize.width > 0 && aSize.height > 0);
 
   int bufSize
     = ImageDataSerializer::ComputeMinBufferSize(aSize, mFormat);
   if (!Allocate(bufSize)) {
     return false;
   }
 
   if (aFlags & ALLOC_CLEAR_BUFFER) {