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:
20161124
Credit:
This bug was discovered by Agostino Sarubbo of Gentoo.
CVE:
CVE-2016-8680
Timeline:
2016-10-03: bug discovered
2016-10-03: bug reported privately to upstream
2016-10-03: upstream released a patch
2016-10-04: blog post about the issue
2016-10-16: CVE Assigned
2016-11-24: upstream released 20161124
Note:
This bug was found with American Fuzzy Lop.
Permalink:
libdwarf: heap-based buffer overflow in _dwarf_get_abbrev_for_code (dwarf_util.c)