[JBIG2] Ensure that the decodeInteger function returns valid integers (issue 15942)

The JBIG2 images in this PDF document are corrupt enough that even Adobe Reader warns about it when opening the file.
*Please note:* I don't really know the JBIG2 image format at all, however from a very brief look at the specification it seems that integers should be 32-bit.

src/core/jbig2.js

@@ -52,6 +52,9 @@ class DecodingContext {
   }
 }
 
+const MAX_INT_32 = 2 ** 31 - 1;
+const MIN_INT_32 = -(2 ** 31);
+
 // Annex A. Arithmetic Integer Decoding Procedure
 // A.2 Procedure for decoding values
 function decodeInteger(contextCache, procedure, decoder) {
@@ -83,10 +86,15 @@ function decodeInteger(contextCache, procedure, decoder) {
                   readBits(4) + 4) :
                 readBits(2);
   /* eslint-enable no-nested-ternary */
+  let signedValue;
   if (sign === 0) {
-    return value;
+    signedValue = value;
   } else if (value > 0) {
-    return -value;
+    signedValue = -value;
+  }
+  // Ensure that the integer value doesn't underflow or overflow.
+  if (signedValue >= MIN_INT_32 && signedValue <= MAX_INT_32) {
+    return signedValue;
   }
   return null;
 }

test/pdfs/issue15942.pdf.link

@@ -0,0 +1 @@
+https://github.com/mozilla/pdf.js/files/10455335/3024388_99997342-a484-416f-9eb9-9a796ada1e2c.pdf

test/test_manifest.json

@@ -2002,6 +2002,14 @@
        "rounds": 1,
        "type": "eq"
     },
+    {  "id": "issue15942",
+       "file": "pdfs/issue15942.pdf",
+       "md5": "d690e16e6a3a8486ebf7289a9c43ba39",
+       "rounds": 1,
+       "link": true,
+       "lastPage": 1,
+       "type": "eq"
+    },
     {  "id": "bug1046314",
        "file": "pdfs/bug1046314.pdf",
        "md5": "fc658439f44cd2dd27c8bee7e7a8344e",