commit 0f284da9239a11e5c23c22222ccdc5babcbd0f7d
author John Reck <jreck@google.com> Wed Jul 14 14:24:51 2021 -0400
committer John Reck <jreck@google.com> Wed Jul 14 14:26:14 2021 -0400
tree f0170a97adba80c67ff6d158879e22f41ff1fdac
parent ab7b0e89918d8db03830378d5520076cd0a2b970

Avoid sampling outside BQ crop rect

The region outside of the BQ crop rect is potentially
garbage. Avoid sampling from it.

Fixes: 189656466
Test: CTS PixelCopyTests & DecodeAccuracyTest
Change-Id: I2910d93471f08aaf807ac9f87fdf84cf29cf4143

libs/hwui/Readback.cpp

diff --git a/libs/hwui/Readback.cpp b/libs/hwui/Readback.cpp
index d8735ce..a743d30 100644
--- a/libs/hwui/Readback.cpp
+++ b/libs/hwui/Readback.cpp
@@ -183,8 +183,10 @@
     SkPaint paint;
     paint.setAlpha(255);
     paint.setBlendMode(SkBlendMode::kSrc);
-    canvas->drawImageRect(image, imageSrcRect, imageDstRect, sampling, &paint,
-                          SkCanvas::kFast_SrcRectConstraint);
+    const bool hasBufferCrop = cropRect.left < cropRect.right && cropRect.top < cropRect.bottom;
+    auto constraint =
+            hasBufferCrop ? SkCanvas::kStrict_SrcRectConstraint : SkCanvas::kFast_SrcRectConstraint;
+    canvas->drawImageRect(image, imageSrcRect, imageDstRect, sampling, &paint, constraint);
     canvas->restore();
 
     if (!tmpSurface->readPixels(*bitmap, 0, 0)) {