Merge pull request #11059 from Snuffleupagus/boundingBox-more-validation

Fallback gracefully when encountering corrupt PDF files with empty /MediaBox and /CropBox entries

src/core/document.js

@@ -95,24 +95,28 @@ class Page {
                   this._getInheritableProperty('Resources') || Dict.empty);
   }
 
-  get mediaBox() {
+  _getBoundingBox(name) {
-    const mediaBox = this._getInheritableProperty('MediaBox',
+    const box = this._getInheritableProperty(name, /* getArray = */ true);
-                                                  /* getArray = */ true);
+
-    // Reset invalid media box to letter size.
+    if (Array.isArray(box) && box.length === 4) {
-    if (!Array.isArray(mediaBox) || mediaBox.length !== 4) {
+      if ((box[2] - box[0]) !== 0 && (box[3] - box[1]) !== 0) {
-      return shadow(this, 'mediaBox', LETTER_SIZE_MEDIABOX);
+        return box;
+      }
+      warn(`Empty /${name} entry.`);
     }
-    return shadow(this, 'mediaBox', mediaBox);
+    return null;
+  }
+
+  get mediaBox() {
+    // Reset invalid media box to letter size.
+    return shadow(this, 'mediaBox',
+                  this._getBoundingBox('MediaBox') || LETTER_SIZE_MEDIABOX);
   }
 
   get cropBox() {
-    const cropBox = this._getInheritableProperty('CropBox',
-                                                 /* getArray = */ true);
     // Reset invalid crop box to media box.
-    if (!Array.isArray(cropBox) || cropBox.length !== 4) {
+    return shadow(this, 'cropBox',
-      return shadow(this, 'cropBox', this.mediaBox);
+                  this._getBoundingBox('CropBox') || this.mediaBox);
-    }
-    return shadow(this, 'cropBox', cropBox);
   }
 
   get userUnit() {
@@ -129,12 +133,18 @@ class Page {
     // extend beyond the boundaries of the media box. If they do, they are
     // effectively reduced to their intersection with the media box."
     const { cropBox, mediaBox, } = this;
+    let view;
     if (cropBox === mediaBox || isArrayEqual(cropBox, mediaBox)) {
-      return shadow(this, 'view', mediaBox);
+      view = mediaBox;
+    } else {
+      const box = Util.intersect(cropBox, mediaBox, /* skipEmpty = */ true);
+      if (box) {
+        view = box;
+      } else {
+        warn('Empty /CropBox and /MediaBox intersection.');
+      }
     }
-
+    return shadow(this, 'view', view || mediaBox);
-    const intersection = Util.intersect(cropBox, mediaBox);
-    return shadow(this, 'view', intersection || mediaBox);
   }
 
   get rotate() {

src/shared/util.js

@@ -748,7 +748,7 @@ var Util = (function UtilClosure() {
   // Returns a rectangle [x1, y1, x2, y2] corresponding to the
   // intersection of rect1 and rect2. If no intersection, returns 'false'
   // The rectangle coordinates of rect1, rect2 should be [x1, y1, x2, y2]
-  Util.intersect = function Util_intersect(rect1, rect2) {
+  Util.intersect = function Util_intersect(rect1, rect2, skipEmpty = false) {
     function compare(a, b) {
       return a - b;
     }
@@ -768,7 +768,7 @@ var Util = (function UtilClosure() {
       result[0] = orderedX[1];
       result[2] = orderedX[2];
     } else {
-      return false;
+      return null;
     }
 
     // Y: first and second points belong to different rectangles?
@@ -778,9 +778,13 @@ var Util = (function UtilClosure() {
       result[1] = orderedY[1];
       result[3] = orderedY[2];
     } else {
-      return false;
+      return null;
     }
 
+    if (skipEmpty &&
+        ((result[2] - result[0]) === 0 || (result[3] - result[1]) === 0)) {
+      return null;
+    }
     return result;
   };
 

test/pdfs/.gitignore

@@ -1,6 +1,7 @@
 *.pdf
 *.error
 
+!boundingBox_invalid.pdf
 !tracemonkey.pdf
 !TrueType_without_cmap.pdf
 !franz.pdf

test/pdfs/boundingBox_invalid.pdf

@@ -0,0 +1,130 @@
+%PDF-1.7
+%âãÏÓ
+1 0 obj 
+<<
+/Pages 2 0 R
+/Type /Catalog
+>>
+endobj 
+2 0 obj 
+<<
+/Kids [3 0 R 4 0 R 5 0 R]
+/Type /Pages
+/Count 3
+>>
+endobj 
+3 0 obj 
+<<
+/Parent 2 0 R
+/Resources 
+<<
+/Font 
+<<
+/F1 6 0 R
+>>
+>>
+/MediaBox [0 0 0 0]
+/Type /Page
+/Contents 7 0 R
+>>
+endobj 
+4 0 obj 
+<<
+/CropBox [0 0 0 0]
+/Parent 2 0 R
+/Resources 
+<<
+/Font 
+<<
+/F1 6 0 R
+>>
+>>
+/MediaBox [0 0 800 600]
+/Type /Page
+/Contents 8 0 R
+>>
+endobj 
+5 0 obj 
+<<
+/CropBox [600 800 1000 1000]
+/Parent 2 0 R
+/Resources 
+<<
+/Font 
+<<
+/F1 6 0 R
+>>
+>>
+/MediaBox [0 0 600 800]
+/Type /Page
+/Contents 9 0 R
+>>
+endobj 
+6 0 obj 
+<<
+/BaseFont /Times-Roman
+/Subtype /Type1
+/Type /Font
+/Encoding /WinAnsiEncoding
+>>
+endobj 
+7 0 obj 
+<<
+/Length 48
+>>
+stream
+BT
+25 700 TD
+/F1 30 Tf
+(Empty /MediaBox) Tj
+ET
+
+
+endstream 
+endobj 
+8 0 obj 
+<<
+/Length 46
+>>
+stream
+BT
+25 500 TD
+/F1 30 Tf
+(Empty /CropBox) Tj
+ET
+
+endstream 
+endobj 
+9 0 obj 
+<<
+/Length 73
+>>
+stream
+BT
+25 700 TD
+/F1 30 Tf
+(Empty /CropBox and /MediaBox intersection) Tj
+ET
+
+endstream 
+endobj xref
+0 10
+0000000000 65535 f 
+0000000015 00000 n 
+0000000066 00000 n 
+0000000137 00000 n 
+0000000263 00000 n 
+0000000412 00000 n 
+0000000571 00000 n 
+0000000672 00000 n 
+0000000773 00000 n 
+0000000872 00000 n 
+trailer
+
+<<
+/Root 1 0 R
+/Size 10
+>>
+startxref
+997
+%%EOF

test/test_manifest.json

@@ -39,6 +39,13 @@
        "lastPage": 1,
        "type": "text"
     },
+    {  "id": "boundingBox_invalid",
+       "file": "pdfs/boundingBox_invalid.pdf",
+       "md5": "f6dfc471bf43abac00cdcf05d81cb070",
+       "rounds": 1,
+       "link": false,
+       "type": "eq"
+    },
     {  "id": "issue11016",
        "file": "pdfs/issue11016_reduced.pdf",
        "md5": "b75578bd052d2e6acdcc85b615eab6b1",

test/unit/api_spec.js

@@ -1065,9 +1065,35 @@ describe('api', function() {
     it('gets userUnit', function () {
       expect(page.userUnit).toEqual(1.0);
     });
-    it('gets view', function () {
+
+    it('gets view', function() {
       expect(page.view).toEqual([0, 0, 595.28, 841.89]);
     });
+    it('gets view, with empty/invalid bounding boxes', function(done) {
+      const viewLoadingTask = getDocument(buildGetDocumentParams(
+        'boundingBox_invalid.pdf'));
+
+      viewLoadingTask.promise.then((pdfDoc) => {
+        const numPages = pdfDoc.numPages;
+        expect(numPages).toEqual(3);
+
+        const viewPromises = [];
+        for (let i = 0; i < numPages; i++) {
+          viewPromises[i] = pdfDoc.getPage(i + 1).then((pdfPage) => {
+            return pdfPage.view;
+          });
+        }
+
+        Promise.all(viewPromises).then(([page1, page2, page3]) => {
+          expect(page1).toEqual([0, 0, 612, 792]);
+          expect(page2).toEqual([0, 0, 800, 600]);
+          expect(page3).toEqual([0, 0, 600, 800]);
+
+          viewLoadingTask.destroy().then(done);
+        });
+      }).catch(done.fail);
+    });
+
     it('gets viewport', function () {
       var viewport = page.getViewport({ scale: 1.5, rotation: 90, });
       expect(viewport.viewBox).toEqual(page.view);