Created attachment 1537439 [details]
Input triggering the bug

Description of problem:
Some inputs may trigger a segmentation fault when running jhead.

Version-Release number of selected component (if applicable):
jhead-3.03

How reproducible:
Stable

Steps to Reproduce:
1. Run jhead with the attached input

Actual results:
Program output:
Header missing JFIF marker
Jfif header too short

Nonfatal Error : 'OOBR_unknown_1_crash' Extraneous 17 padding bytes before section ED

Nonfatal Error : 'OOBR_unknown_1_crash' Extraneous 24 padding bytes before section D5
File name    : OOBR_unknown_1_crash
File size    : 127 bytes
File date    : 2019:02:21 05:45:58
Resolution   : 0 x 0
Color/bw     : Black and white
Jpeg process : Unknown
======= IPTC data: =======
Headline      : "2Q                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
[1]    436 segmentation fault (core dumped)  jhead OOBR_unknown_1_crash"

Crashed at:
Core was generated by `jhead OOBR_unknown_1_crash'.
Program terminated with signal 11, Segmentation fault.
#0  show_IPTC (Data=<optimized out>, itemlen=<optimized out>) at iptc.c:122
122             signature = (*pos << 8) + (*(pos+1));

Backtrace:
#0  show_IPTC (Data=<optimized out>, itemlen=<optimized out>) at iptc.c:122
#1  0x0000000000402bdd in ProcessFile (FileName=0x7ffe9cd77908 "OOBR_unknown_1_crash") at jhead.c:955
#2  0x00000000004017e4 in main (argc=<optimized out>, argv=0x7ffe9cd76c18) at jhead.c:1757`

Expected results:
Not applicable

Additional info: