Merge pull request #19356 from Snuffleupagus/bug-1942064-2

Replace the EXIF-block with dummy data to prevent JPEG images being rotated (bug 1942064)

src/core/jpg.js

@@ -817,6 +817,29 @@ class JpegImage {
 
     markerLoop: while (fileMarker !== /* EOI (End of Image) = */ 0xffd9) {
       switch (fileMarker) {
+        case 0xffe1: // APP1 - Exif
+          // TODO: Remove this once https://github.com/w3c/webcodecs/issues/870
+          //       is fixed.
+          const { appData, newOffset } = readDataBlock(data, offset);
+          offset = newOffset;
+
+          // 'Exif\x00\x00'
+          if (
+            appData[0] === 0x45 &&
+            appData[1] === 0x78 &&
+            appData[2] === 0x69 &&
+            appData[3] === 0x66 &&
+            appData[4] === 0 &&
+            appData[5] === 0
+          ) {
+            // Replace the entire EXIF-block with dummy data, to ensure that a
+            // non-default EXIF orientation won't cause the image to be rotated
+            // when using `ImageDecoder` (fixes bug1942064.pdf).
+            appData.fill(0x00, 6);
+          }
+          fileMarker = readUint16(data, offset);
+          offset += 2;
+          continue;
         case 0xffc0: // SOF0 (Start of Frame, Baseline DCT)
         case 0xffc1: // SOF1 (Start of Frame, Extended DCT)
         case 0xffc2: // SOF2 (Start of Frame, Progressive DCT)

test/pdfs/.gitignore

@@ -503,6 +503,7 @@
 !annotation-line-without-appearance.pdf
 !bug1669099.pdf
 !annotation-square-circle.pdf
+!bug1942064.pdf
 !annotation-square-circle-without-appearance.pdf
 !annotation-stamp.pdf
 !issue14048.pdf

test/test_manifest.json

@@ -8997,6 +8997,13 @@
     "link": true,
     "type": "other"
   },
+  {
+    "id": "bug1942064",
+    "file": "pdfs/bug1942064.pdf",
+    "md5": "d50b5ebb8cab1211609d16faa54ec47d",
+    "rounds": 1,
+    "type": "eq"
+  },
   {
     "id": "issue16221-text",
     "file": "pdfs/issue16221.pdf",