From 4acea512f36b96256535b45b1a7e723c61c89c31 Mon Sep 17 00:00:00 2001
From: Carl Eugen Hoyos <cehoyos@ag.or.at>
Date: Sun, 1 Jan 2017 14:19:48 +0100
Subject: [PATCH] lavc/mjpegdec: Do not overread too short JFIF tags.

Fixes ticket #6055.
---
 libavcodec/mjpegdec.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index eee8d58147..e0b22ec948 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -1670,6 +1670,8 @@ static int mjpeg_decode_app(MJpegDecodeContext *s)
 
     if (id == AV_RB32("JFIF")) {
         int t_w, t_h, v1, v2;
+        if (len < 8)
+            goto out;
         skip_bits(&s->gb, 8); /* the trailing zero-byte */
         v1 = get_bits(&s->gb, 8);
         v2 = get_bits(&s->gb, 8);