Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <2323220.oXSkLC07fN@arcadia>
Date: Sat, 08 Oct 2016 22:16:25 +0200
From: Agostino Sarubbo <ago@...too.org>
To: oss-security@...ts.openwall.com
Subject: libdwarf: heap-based buffer overflow in _dwarf_get_abbrev_for_code (dwarf_util.c)

Description:
libdwarf is a library to consume and produce DWARF debug information.

A fuzzing revealed an out bounds read,

The complete ASan output:

# dwarfdump $FILE
==30323==ERROR: AddressSanitizer: heap-buffer-overflow on address 
0x611000005a00 at pc 0x000000606e87 bp 0x7ffe35e5e5b0 sp 0x7ffe35e5e5a8
READ of size 1 at 0x611000005a00 thread T0
    #0 0x606e86 in _dwarf_get_abbrev_for_code 
/tmp/dwarf-20161001/libdwarf/dwarf_util.c:624:43
    #1 0x576086 in dwarf_siblingof_b 
/tmp/dwarf-20161001/libdwarf/dwarf_die_deliv.c:1628:12
    #2 0x517e73 in print_die_and_children_internal 
/tmp/dwarf-20161001/dwarfdump/print_die.c:1163:17
    #3 0x517c6b in print_die_and_children_internal 
/tmp/dwarf-20161001/dwarfdump/print_die.c:1142:13
    #4 0x5147cc in print_die_and_children 
/tmp/dwarf-20161001/dwarfdump/print_die.c:921:5
    #5 0x5147cc in print_one_die_section 
/tmp/dwarf-20161001/dwarfdump/print_die.c:831
    #6 0x512262 in print_infos 
/tmp/dwarf-20161001/dwarfdump/print_die.c:371:16
    #7 0x4faaea in process_one_file 
/tmp/dwarf-20161001/dwarfdump/dwarfdump.c:1371:9
    #8 0x4faaea in main /tmp/dwarf-20161001/dwarfdump/dwarfdump.c:654
    #9 0x7f5912c2361f in __libc_start_main /var/tmp/portage/sys-
libs/glibc-2.22-r4/work/glibc-2.22/csu/libc-start.c:289
    #10 0x419588 in _start (/usr/bin/dwarfdump-asan+0x419588)

0x611000005a00 is located 0 bytes to the right of 256-byte region 
[0x611000005900,0x611000005a00)
allocated by thread T0 here:
    #0 0x4c0ad8 in malloc /var/tmp/portage/sys-devel/llvm-3.8.1-
r2/work/llvm-3.8.1.src/projects/compiler-rt/lib/asan/asan_malloc_linux.cc:52
    #1 0x7f5913cfd206 in __libelf_set_rawdata_wrlock /tmp/portage/dev-
libs/elfutils-0.166/work/elfutils-0.166/libelf/elf_getdata.c:318

SUMMARY: AddressSanitizer: heap-buffer-overflow 
/tmp/dwarf-20161001/libdwarf/dwarf_util.c:624:43 in _dwarf_get_abbrev_for_code
Shadow bytes around the buggy address:
  0x0c227fff8af0: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
  0x0c227fff8b00: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c227fff8b10: fd fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c227fff8b20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c227fff8b30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c227fff8b40:[fa]fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x0c227fff8b50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c227fff8b60: 00 fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c227fff8b70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c227fff8b80: 00 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa
  0x0c227fff8b90: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
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
==30323==ABORTING

Affected version:
20161001 and past

Fixed version:
N/A

Commit fix:
https://sourceforge.net/p/libdwarf/code/ci/268c1f18d1d28612af3b72d7c670076b1b88e51c/tree/libdwarf/dwarf_util.c?diff=0b28b923c3bd9827d1d904feed2abadde4fa5de2

Credit:
This bug was discovered by Agostino Sarubbo of Gentoo.

Timeline:
2016-10-03: bug discovered
2016-10-03: bug reported privately to upstream
2016-10-03: upstream realeased a patch
2016-10-04: blog post about the issue

Note:
This bug was found with American Fuzzy Lop.

Permalink:
https://blogs.gentoo.org/ago/2016/10/04/libdwarf-heap-based-buffer-overflow-in-_dwarf_get_abbrev_for_code-dwarf_util-c/

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.