[bug-libextractor] Infinite loop in libextractor

[黄金]

Problem:
The extract tool entered infinite loop while extracting a malformed file.


Tested Version:
extract v1.6

System Information:
Ubuntu 16.04.4 LTS \n \l

Details:
The extract tool entered infinite loop while parsing an malformed file.

address@hidden:~/Desktop$ extract 
timeout-0d2eb1d040e384e7004cf036eac03152a4472d14
Keywords for file timeout-0d2eb1d040e384e7004cf036eac03152a4472d14:
mimetype - application/octet-stream
mimetype - video/mpeg
image dimensions - 320x240
format version - MPEG1
mimetype - video/mpeg
image dimensions - 320x240
format version - MPEG1
mimetype - video/mpeg
image dimensions - 320x240
format version - MPEG1
mimetype - video/mpeg
image dimensions - 320x240
format version - MPEG1
mimetype - video/mpeg
image dimensions - 320x240
........

infinite printing. 

This was found by Libfuzzer.

CREDIT:
ADLab of Venustech