[FFmpeg-trac] #8309(undetermined:new): heap-buffer-overflow at libavfilter/drawutils.c:341

[FFmpeg]

#8309: heap-buffer-overflow at libavfilter/drawutils.c:341
-------------------------------------+-------------------------------------
             Reporter:  Suhwan       |                     Type:  defect
               Status:  new          |                 Priority:  important
            Component:               |                  Version:  git-
  undetermined                       |  master
             Keywords:  asan         |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 There is a heap-buffer-overflow at libavfilter/drawutils.c:341 in
 ff_fill_rectangle

 I compiled ffmpeg with "--toolchain=clang-asan" to check the memory
 corruption and attached log file.
 How to reproduce:
 {{{
 % ffmpeg_g -y -i $PoC  -filter_complex oscilloscope tmp.mp3

 ffmpeg version N-95450-g1d479300cb Copyright (c) 2000-2019 the FFmpeg
 developers
 built with clang version 6.0.0-1ubuntu2 (tags/RELEASE_600/final)
 configuration: --cc=clang --cxx=clang++ --ld=clang --enable-debug
 --toolchain=clang-asan
 }}}

 Here's ASAN log

 {{{
 =================================================================
 ==8790==ERROR: AddressSanitizer: heap-buffer-overflow on address
 0x611000001180 at pc 0x0000004dcadc bp 0x7ffc64ef8590 sp 0x7ffc64ef7d40
 WRITE of size 4 at 0x611000001180 thread T0
     #0 0x4dcadb in __asan_memcpy (ffmpeg_g+0x4dcadb)
     #1 0x1b12aad in ff_fill_rectangle
 ffmpeg/libavfilter/drawutils.c:341:13
     #2 0xbdb58b in oscilloscope_filter_frame
 ffmpeg/libavfilter/vf_datascope.c:981:13
     #3 0x827129 in ff_filter_activate_default
 ffmpeg/libavfilter/avfilter.c:1084:11
     #4 0x827129 in ff_filter_activate ffmpeg/libavfilter/avfilter.c:1443
     #5 0x86ffd5 in push_frame ffmpeg/libavfilter/buffersrc.c:187:15
     #6 0x86ffd5 in av_buffersrc_add_frame_internal
 ffmpeg/libavfilter/buffersrc.c:261
     #7 0x86ea62 in av_buffersrc_add_frame_flags
 ffmpeg/libavfilter/buffersrc.c:170:16
     #8 0x666467 in ifilter_send_frame ffmpeg/fftools/ffmpeg.c:2186:11
     #9 0x666467 in send_frame_to_filters ffmpeg/fftools/ffmpeg.c:2260
     #10 0x6076c6 in decode_video ffmpeg/fftools/ffmpeg.c:2459:11
     #11 0x6076c6 in process_input_packet ffmpeg/fftools/ffmpeg.c:2613
     #12 0x64a767 in process_input ffmpeg/fftools/ffmpeg.c:4508:5
     #13 0x5e71b7 in transcode_step ffmpeg/fftools/ffmpeg.c:4628:11
     #14 0x5e71b7 in transcode ffmpeg/fftools/ffmpeg.c:4682
     #15 0x5db6bb in main ffmpeg/fftools/ffmpeg.c:4884:9
     #16 0x7fb30df9cb96 in __libc_start_main /build/glibc-
 OTsEL5/glibc-2.27/csu/../csu/libc-start.c:310
     #17 0x41def9 in _start (ffmpeg_g+0x41def9)

 0x611000001180 is located 64 bytes to the left of 143-byte region
 [0x6110000011c0,0x61100000124f)
 allocated by thread T0 here:
     #0 0x4de9e8 in posix_memalign (ffmpeg_g+0x4de9e8)
     #1 0x85c4251 in av_malloc ffmpeg/libavutil/mem.c:87:9
     #2 0x852b181 in av_buffer_alloc ffmpeg/libavutil/buffer.c:72:12
     #3 0x852b181 in av_buffer_allocz ffmpeg/libavutil/buffer.c:85
     #4 0x852f9a6 in pool_alloc_buffer ffmpeg/libavutil/buffer.c:313:26
     #5 0x852f9a6 in av_buffer_pool_get ffmpeg/libavutil/buffer.c:349
     #6 0x2ef33d2 in video_get_buffer ffmpeg/libavcodec/decode.c:1678:23
     #7 0x2ef33d2 in avcodec_default_get_buffer2
 ffmpeg/libavcodec/decode.c:1717
     #8 0x2efaedc in get_buffer_internal ffmpeg/libavcodec/decode.c:1945:11
     #9 0x2efaedc in ff_get_buffer ffmpeg/libavcodec/decode.c:1970

 SUMMARY: AddressSanitizer: heap-buffer-overflow (ffmpeg_g+0x4dcadb) in
 __asan_memcpy
 Shadow bytes around the buggy address:
   0x0c227fff81e0: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
   0x0c227fff81f0: 00 00 00 00 00 00 00 00 00 00 fa fa fa fa fa fa
   0x0c227fff8200: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
   0x0c227fff8210: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
   0x0c227fff8220: 00 00 fa fa fa fa fa fa fa fa fa fa fa fa fa fa
 =>0x0c227fff8230:[fa]fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
   0x0c227fff8240: 00 00 00 00 00 00 00 00 00 07 fa fa fa fa fa fa
   0x0c227fff8250: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
   0x0c227fff8260: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
   0x0c227fff8270: 00 00 00 fa fa fa fa fa fa fa fa fa fa fa fa fa
   0x0c227fff8280: 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
   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
 ==8790==ABORTING

 }}}
 Please confirm.
 Thanks

--
Ticket URL: <https://trac.ffmpeg.org/ticket/8309>
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