commit 4a72c19f8861c59f23bd075ac665fe49e3dd0a40
author Ram Mohan <ram.mohan@ittiam.com> Mon May 22 19:05:06 2023 +0530
committer Dichen Zhang <dichenzhang@google.com> Wed May 31 20:47:25 2023 +0000
tree 879747dd4ccd0d7b6776efdbe9557b1c40cdf4d7
parent 6bd58d4d045fab777551175e0d16fb9c5f22c0cb

ultrahdr: compress image reads outside bounds for non aligned widths

jpeg_write_raw_data() processes one MCU row per call, and thus one must
pass buffer of at least max_v_samp_factor * DCTSIZE scanlines. The
buffer must be large enough to hold the actual data plus padding
to DCT-block boundaries.

Bug: 284117683
Test: ./ultrahdr_enc_fuzzer

Change-Id: I993773817bf3805463bb21bb977624d6c2d45a0b

libs/ultrahdr/tests/jpegencoderhelper_test.cpp

diff --git a/libs/ultrahdr/tests/jpegencoderhelper_test.cpp b/libs/ultrahdr/tests/jpegencoderhelper_test.cpp
index 8f18ac0..f0e1fa4 100644
--- a/libs/ultrahdr/tests/jpegencoderhelper_test.cpp
+++ b/libs/ultrahdr/tests/jpegencoderhelper_test.cpp
@@ -108,18 +108,9 @@
     ASSERT_GT(encoder.getCompressedImageSize(), static_cast<uint32_t>(0));
 }
 
-// The width of the "unaligned" image is not 16-aligned, and will fail if encoded directly.
-// Should pass with the padding zero method.
 TEST_F(JpegEncoderHelperTest, encodeUnalignedImage) {
     JpegEncoderHelper encoder;
-    const size_t paddingZeroLength = JpegEncoderHelper::kCompressBatchSize
-            * JpegEncoderHelper::kCompressBatchSize / 4;
-    std::unique_ptr<uint8_t[]> imageWithPaddingZeros(
-            new uint8_t[UNALIGNED_IMAGE_WIDTH * UNALIGNED_IMAGE_HEIGHT * 3 / 2
-            + paddingZeroLength]);
-    memcpy(imageWithPaddingZeros.get(), mUnalignedImage.buffer.get(),
-            UNALIGNED_IMAGE_WIDTH * UNALIGNED_IMAGE_HEIGHT * 3 / 2);
-    EXPECT_TRUE(encoder.compressImage(imageWithPaddingZeros.get(), mUnalignedImage.width,
+    EXPECT_TRUE(encoder.compressImage(mUnalignedImage.buffer.get(), mUnalignedImage.width,
                                       mUnalignedImage.height, JPEG_QUALITY, NULL, 0));
     ASSERT_GT(encoder.getCompressedImageSize(), static_cast<uint32_t>(0));
 }