#38 ASan: heap-buffer-overflow ./src/otsu.c:272 in thresholding

[Henri Salo]

Tested version: 0.50
Credit: Henri Salo

 ERROR reading at head+1*4
# threshold: Value<=gmin
=================================================================
==11692==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x61f00000fa1a at pc 0x5613bbbbb885 bp 0x7ffc8b985190 sp 0x7ffc8b985188
READ of size 1 at 0x61f00000fa1a thread T0
    #0 0x5613bbbbb884 in thresholding /home/hsalo/src/gocr-0.50/src/otsu.c:272
    #1 0x5613bbaa7346 in pgm2asc /home/hsalo/src/gocr-0.50/src/pgm2asc.c:3072
    #2 0x5613bba5f84b in main /home/hsalo/src/gocr-0.50/src/gocr.c:373
    #3 0x7efd133f52e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
    #4 0x5613bba61919 in _start (/home/hsalo/builds/gocr/0.50/bin/gocr+0x17919)

0x61f00000fa1a is located 0 bytes to the right of 2970-byte region [0x61f00000ee80,0x61f00000fa1a)
allocated by thread T0 here:
    #0 0x7efd13b39d28 in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.3+0xc1d28)
    #1 0x5613bbbe6154 in readpgm /home/hsalo/src/gocr-0.50/src/pnm.c:371

SUMMARY: AddressSanitizer: heap-buffer-overflow /home/hsalo/src/gocr-0.50/src/otsu.c:272 in thresholding
Shadow bytes around the buggy address:
  0x0c3e7fff9ef0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c3e7fff9f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c3e7fff9f10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c3e7fff9f20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c3e7fff9f30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c3e7fff9f40: 00 00 00[02]fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c3e7fff9f50: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c3e7fff9f60: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c3e7fff9f70: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c3e7fff9f80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c3e7fff9f90: 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
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==11692==ABORTING

[Henri Salo]

Actually someone already reported same issue in: https://bugs.debian.org/889224