signed integer overflow in update_initial_timestamps()

[tsmith]

Summary of the bug:
UBSan: libavformat/utils.c:925:40: runtime error: signed integer overflow: -9223372036854775806 - 9223090561878065151 cannot be represented in type 'long long'

How to reproduce:

% ffmpeg -f ivf -i <test_case> -f null -
ffmpeg version N-77718-g72673ad Copyright (c) 2000-2016 the FFmpeg developers
  built with Ubuntu clang version 3.7.1-svn253742-1~exp1 (branches/release_37) (based on LLVM 3.7.1)
  configuration: --cc=clang --cxx=clang++ --disable-libxcb --disable-xlib --disable-logging --disable-ffprobe --disable-ffplay --disable-sdl --disable-ffserver --disable-doc --disable-pthreads --disable-network --disable-d3d11va --disable-dxva2 --disable-vaapi --disable-vda --disable-vdpau --disable-stripping --disable-runtime-cpudetect --disable-securetransport --disable-iconv
  libavutil      55. 12.100 / 55. 12.100
  libavcodec     57. 22.100 / 57. 22.100
  libavformat    57. 21.101 / 57. 21.101
  libavdevice    57.  0.100 / 57.  0.100
  libavfilter     6. 23.100 /  6. 23.100
  libswscale      4.  0.100 /  4.  0.100
  libswresample   2.  0.101 /  2.  0.101
[vp9 @ 0x619000005a80] Warning: not compiled with thread support, using thread emulation
[vp9 @ 0x619000005a80] Invalid compressed header size
Truncating packet of size 1347813408 to 4
libavformat/utils.c:925:40: runtime error: signed integer overflow: -9223372036854775806 - 9223090561878065151 cannot be represented in type 'long long'
    #0 0xc368ef in update_initial_timestamps /home/user/code/ffmpeg/libavformat/utils.c:925:40
    #1 0xc3440b in compute_pkt_fields /home/user/code/ffmpeg/libavformat/utils.c:1163:13
    #2 0xc31ef6 in parse_packet /home/user/code/ffmpeg/libavformat/utils.c:1291:9
    #3 0xc11bed in read_frame_internal /home/user/code/ffmpeg/libavformat/utils.c:1406:24
    #4 0xc1e563 in avformat_find_stream_info /home/user/code/ffmpeg/libavformat/utils.c:3293:15
    #5 0x53c6cb in open_input_file /home/user/code/ffmpeg/ffmpeg_opt.c:970:11
    #6 0x53a94f in open_files /home/user/code/ffmpeg/ffmpeg_opt.c:2999:15
    #7 0x53a11c in ffmpeg_parse_options /home/user/code/ffmpeg/ffmpeg_opt.c:3036:11
    #8 0x56f5ab in main /home/user/code/ffmpeg/ffmpeg.c:4292:11
    #9 0x7fac101c9ec4 in __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287
    #10 0x466445 in _start (/home/user/Desktop/ffmpeg/ffmpeg_full+0x466445)

[Michael Niedermayer]

Fixed in e936c8d176efd1a0a41e22df24564b1178c79ea9

[Carl Eugen Hoyos]

I probably reopened this ticket by mistake, my original patch was:
https://ffmpeg.org/pipermail/ffmpeg-devel/2016-September/199994.html