Description
system info
Ubuntu x86_64, clang 6.0, dwg2dxf(0.12.4.4608)
Command line
./programs/dwg2dxf -b -m @@ -o /dev/null
AddressSanitizer output
==9543==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fffffffc8f0 at pc 0x0000007257bb bp 0x7fffffffbc90 sp 0x7fffffffbc88
WRITE of size 1 at 0x7fffffffc8f0 thread T0
#0 0x7257ba in copy_bytes /testcase/libredwg/src/decode_r2007.c:228:12
#1 0x7257ba in decompress_r2007 /testcase/libredwg/src/decode_r2007.c:563
#2 0x712263 in read_file_header /testcase/libredwg/src/decode_r2007.c:1247:13
#3 0x712263 in read_r2007_meta_data /testcase/libredwg/src/decode_r2007.c:2354
#4 0x533116 in decode_R2007 /testcase/libredwg/src/decode.c:3231:11
#5 0x533116 in dwg_decode /testcase/libredwg/src/decode.c:212
#6 0x50d759 in dwg_read_file /testcase/libredwg/src/dwg.c:254:11
#7 0x50c454 in main /testcase/libredwg/programs/dwg2dxf.c:258:15
#8 0x7ffff6e22c86 in __libc_start_main /build/glibc-CVJwZb/glibc-2.27/csu/../csu/libc-start.c:310
#9 0x419ee9 in _start (/testcase/libredwg/programs/dwg2dxf+0x419ee9)
Address 0x7fffffffc8f0 is located in stack of thread T0 at offset 2736 in frame
#0 0x71159f in read_r2007_meta_data /testcase/libredwg/src/decode_r2007.c:2338
This frame has 23 object(s):
[32, 40) 'acis_sab_data.i.i'
[64, 65) 'acis_empty.i.i'
[80, 82) 'version1913.i.i'
[96, 100) 'size1930.i.i'
[112, 160) 'sec_dat.i548'
[192, 240) 'sec_dat.i515'
[272, 320) 'sec_dat.i492'
[352, 400) 'sec_dat.i455'
[432, 480) 'sec_dat.i424'
[512, 560) 'sec_dat.i391'
[592, 640) 'sec_dat.i356'
[672, 720) 'sec_dat.i330'
[752, 800) 'sec_dat.i301'
[832, 836) 'size.i282'
[848, 873) 'old_dat.sroa.0.i'
[912, 960) 'sec_dat.i268'
[992, 1040) 'sec_dat.i220'
[1072, 1120) 'str.i'
[1152, 1200) 'sec_dat.i'
[1232, 1280) 'str_dat.i'
[1312, 1320) 'ptr.i'
[1344, 2328) 'data.i'
[2464, 2736) 'file_header' <== Memory access at offset 2736 overflows this variable
HINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext
(longjmp and C++ exceptions are supported)
SUMMARY: AddressSanitizer: stack-buffer-overflow /testcase/libredwg/src/decode_r2007.c:228:12 in copy_bytes
Shadow bytes around the buggy address:
0x10007fff78c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x10007fff78d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x10007fff78e0: 00 00 00 00 00 00 00 00 00 00 00 f2 f2 f2 f2 f2
0x10007fff78f0: f2 f2 f2 f2 f2 f2 f2 f2 f2 f2 f2 f2 00 00 00 00
0x10007fff7900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x10007fff7910: 00 00 00 00 00 00 00 00 00 00 00 00 00 00[f3]f3
0x10007fff7920: f3 f3 f3 f3 f3 f3 f3 f3 00 00 00 00 00 00 00 00
0x10007fff7930: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x10007fff7940: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x10007fff7950: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x10007fff7960: 00 00 00 00 00 00 00 00 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
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
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
==9543==ABORTING
poc
https://gitee.com/cxlzff/fuzz-poc/raw/master/libredwg/copy_bytes_sof