From 5737c9987ac0d4184dec7dedac60680dca480809 Mon Sep 17 00:00:00 2001
From: Raphael Luba <raphael@leanbyte.com>
Date: Tue, 21 Apr 2020 17:00:55 +0200
Subject: [PATCH] =?UTF-8?q?fix:=20don=E2=80=99t=20fail=20if=20scan=20conta?=
 =?UTF-8?q?ins=20trailing=20bytes=20(#66)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 lib/decoder.js                               |  12 ++++++++++++
 test/fixtures/redbox-with-trailing-bytes.jpg | Bin 0 -> 2225 bytes
 test/index.js                                |   9 +++++++++
 3 files changed, 21 insertions(+)
 create mode 100644 test/fixtures/redbox-with-trailing-bytes.jpg

diff --git a/lib/decoder.js b/lib/decoder.js
index cac42f1..6f1b752 100644
--- a/lib/decoder.js
+++ b/lib/decoder.js
@@ -325,6 +325,18 @@ var JpegImage = (function jpegImage() {
         }
       }
 
+      if (mcu === mcuExpected) {
+        // Skip trailing bytes at the end of the scan - until we reach the next marker
+        do {
+          if (data[offset] === 0xFF) {
+            if (data[offset + 1] !== 0x00) {
+              break;
+            }
+          }
+          offset += 1;
+        } while (offset < data.length - 2);
+      }
+
       // find marker
       bitsCount = 0;
       marker = (data[offset] << 8) | data[offset + 1];
diff --git a/test/fixtures/redbox-with-trailing-bytes.jpg b/test/fixtures/redbox-with-trailing-bytes.jpg
new file mode 100644
index 0000000000000000000000000000000000000000..35bce415f1f6406cce72de77f87ebccf1009b711
GIT binary patch
literal 2225
zcmex=<NpH&0WUXCHwH#V1_nkTWcYuZp@l(!n}?5wOMs7;Pe@QeSVBWeLQG7;P+3)0
z!^+s!#?sir+`%Kp&%q_!)!ZT=H!wUtDLo_I&bP3#Af+NEH9eV8P)JBZR6<`$N<Z1j
z!YP?#@c#gVAP2)1Mh9j_K?Wv4MrJ|A|3?@X0o};T2nGyLz{teR!pg?Z!O6ufz`(@F
z%*@2X%*x8b0#sQGlw)8KWEE00bYv3_Ok`Io6ftU?xR68HY2!iBpo<?=jFXC*IJv~c
zB_yR()zmdKwM<OS%q=XfoLyYq+&w(Kf<r>X!XqN1l2cOC(lau%ic3n%$}1|Xnp;}i
z+B-VCCQY6)b=ve9GiNPYykzOJ<ttXM+O&Dg)@|E&?A&$e@R6g(j-NPr>eA&aSFc^a
zar4&0M~|O8efIpt%U2&ieg5+G+xH(oe=#yJL%ahdAs#~V576U`Oe`$SEbJivFfx?`
zF|!~GtD+&BkYgZwVxh2-Q6q<l)5L`v4{|CS2YnDtD!Rxereg9?^&`kjU>_0Zp(e6?
z1osf!KmTtr@Gvt1BaB&)!JgshdY#_~7BDq%F=#N1QlmjInhHiU!f07AS{#y9Bm4(8
HO>P1J?lcQj

literal 0
HcmV?d00001

diff --git a/test/index.js b/test/index.js
index 0f9313e..e77e66c 100644
--- a/test/index.js
+++ b/test/index.js
@@ -54,6 +54,15 @@ it('should be able to decode a JPEG with RST intervals', function(t) {
   t.end();
 });
 
+it('should be able to decode a JPEG with trailing bytes', function(t) {
+  var jpegData = fixture('redbox-with-trailing-bytes.jpg');
+  var rawImageData = jpeg.decode(jpegData);
+  var expected = fixture('redbox.jpg');
+  var rawExpectedImageData = jpeg.decode(expected);
+  t.deepEqual(rawImageData.data, rawExpectedImageData.data);
+  t.end();
+});
+
 it('should be able to decode a grayscale JPEG', function(t) {
   var jpegData = fixture('apsara.jpg');
   var rawImageData = jpeg.decode(jpegData);