#367 out-of-bounds read in coders/dib.c:706:13

[moshe]

This bug was found while fuzzing graphicsmagick with afl-fuzz

Tested on hg changeset 44ed8318ba6a+

Command: gm convert id:000074,sig:06,src:000371,op:havoc,rep:16 /dev/null

=================================================================
==17760==ERROR: AddressSanitizer: heap-buffer-overflow on address 0xb6200434 at pc 0x083ce568 bp 0xbff93858 sp 0xbff93850
READ of size 4 at 0xb6200434 thread T0
#0 0x83ce567 in ReadDIBImage /home/user/Desktop/graphicsmagick/coders/dib.c:706:13
#1 0x81f84b4 in ReadImage /home/user/Desktop/graphicsmagick/magick/constitute.c:1607:14
#2 0x816fbca in ConvertImageCommand /home/user/Desktop/graphicsmagick/magick/command.c:4348:22
#3 0x8187f6b in MagickCommand /home/user/Desktop/graphicsmagick/magick/command.c:8862:27
#4 0x81cd999 in GMCommandSingle /home/user/Desktop/graphicsmagick/magick/command.c:17338:10
#5 0x81cc6ae in GMCommand /home/user/Desktop/graphicsmagick/magick/command.c:17391:16
#6 0x8139511 in main /home/user/Desktop/graphicsmagick/utilities/gm.c:61:10
#7 0xb754b73d in __libc_start_main /build/glibc-tVsQx_/glibc-2.21/csu/libc-start.c:289
#8 0x807fd9b in _start (/home/user/Desktop/graphicsmagick/utilities/gm+0x807fd9b)

0xb6200434 is located 0 bytes to the right of 4-byte region [0xb6200430,0xb6200434)
allocated by thread T0 here:
#0 0x8117a29 in malloc (/home/user/Desktop/graphicsmagick/utilities/gm+0x8117a29)
#1 0x827e984 in MagickMalloc /home/user/Desktop/graphicsmagick/magick/memory.c:156:11

SUMMARY: AddressSanitizer: heap-buffer-overflow /home/user/Desktop/graphicsmagick/coders/dib.c:706 ReadDIBImage
Shadow bytes around the buggy address:
0x36c40030: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x36c40040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x36c40050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x36c40060: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x36c40070: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
=>0x36c40080: fa fa fd fa fa fa[04]fa fa fa 00 02 fa fa 00 fa
0x36c40090: fa fa fd fd fa fa fd fa fa fa fd fd fa fa fd fa
0x36c400a0: fa fa fd fa fa fa fd fd fa fa fd fa fa fa fd fd
0x36c400b0: fa fa fd fa fa fa fd fa fa fa 00 06 fa fa 00 02
0x36c400c0: fa fa fd fd fa fa 00 04 fa fa fd fd fa fa 00 04
0x36c400d0: fa fa 00 04 fa fa 00 04 fa fa 00 04 fa fa 00 04
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
==17760==ABORTING

[Bob Friesenhahn]

Fixed by Mercurial changeset 14749:e5d25390bce4