heap buffer overflow crashes on memcmp

[Jingqi Long]

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==31124==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60200000eff2 at pc 0x7faf87682676 bp 0x7fff92fb4f10 sp 0x7fff92fb46b8
READ of size 4 at 0x60200000eff2 thread T0
    #0 0x7faf87682675 in memcmp (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x77675)
    #1 0x41c42d in ReadJpegSections /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jpgfile.c:286
    #2 0x41f62d in ReadJpegSections /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jpgfile.c:126
    #3 0x41f62d in ReadJpegFile /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jpgfile.c:379
    #4 0x411987 in ProcessFile /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jhead.c:905
    #5 0x4036ca in main /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jhead.c:1756
    #6 0x7faf8624b83f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
    #7 0x40d498 in _start (/home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jhead+0x40d498)

0x60200000eff2 is located 0 bytes to the right of 2-byte region [0x60200000eff0,0x60200000eff2)
allocated by thread T0 here:
    #0 0x7faf876a3602 in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x98602)
    #1 0x41beaa in ReadJpegSections /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jpgfile.c:173
    #2 0x41f62d in ReadJpegSections /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jpgfile.c:126
    #3 0x41f62d in ReadJpegFile /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jpgfile.c:379
    #4 0x411987 in ProcessFile /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jhead.c:905
    #5 0x4036ca in main /home/mondaylord/Documents/SMSE-AFL/bin/jhead-3.04/jhead.c:1756
    #6 0x7faf8624b83f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)

SUMMARY: AddressSanitizer: heap-buffer-overflow ??:0 memcmp
Shadow bytes around the buggy address:
  0x0c047fff9da0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff9db0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff9dc0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff9dd0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff9de0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
=>0x0c047fff9df0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa[02]fa
  0x0c047fff9e00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff9e10: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff9e20: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff9e30: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff9e40: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable: 00
  Partially addressable: 01 02 03 04 05 06 07
  Heap left redzone: fa
  Heap right redzone: fb
  Freed heap region: fd
  Stack left redzone: f1
  Stack mid redzone: f2
  Stack right redzone: f3
  Stack partial redzone: f4
  Stack after return: f5
  Stack use after scope: f8
  Global redzone: f9
  Global init order: f6
  Poisoned by user: f7
  Container overflow: fc
  Array cookie: ac
  Intra object redzone: bb
  ASan internal: fe
==31124==ABORTING