[FFmpeg-trac] #8323(undetermined:new): signed integer overflow at libavfilter/vf_aspect.c:81

[FFmpeg]

#8323: signed integer overflow at libavfilter/vf_aspect.c:81
-------------------------------------+-------------------------------------
             Reporter:  Suhwan       |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:  git-
  undetermined                       |  master
             Keywords:  ubsan        |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 There're two signed integer overflow at libavfilter/vf_aspect.c:81

 I compiled ffmpeg with "--toolchain=clang-usan" to check the undefined-
 behaviours and attached log file.
 How to reproduce:
 {{{
 % ffmpeg_g -i $PoC -filter_complex setsar -target dv -loglevel 0
 tmp.vc1test

 ffmpeg version N-95517-g0b8956b25c 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-usan
 }}}

 Here's UBSAN log

 {{{
 libavfilter/vf_aspect.c:81:49: runtime error: signed integer overflow:
 1562273630 * 17 cannot be represented in type 'int'

 Thread 1 "ffmpeg_g" hit Breakpoint 1, 0x00000000004288b0 in
 __ubsan::ScopedReport::~ScopedReport() ()
 (gdb) bt
 #0  0x00000000004288b0 in __ubsan::ScopedReport::~ScopedReport() ()
 #1  0x000000000042b0eb in void
 handleIntegerOverflowImpl<__ubsan::Value>(__ubsan::OverflowData*, unsigned
 long, char const*, __ubsan::Value, __ubsan::ReportOptions) ()
 #2  0x000000000042c9df in __ubsan_handle_mul_overflow ()
 #3  0x0000000000695c1f in compute_dar (dar=0x7fffffffbff0, sar=..., w=17,
 h=<optimized out>)
     at libavfilter/vf_aspect.c:81
 #4  0x0000000000695ddf in setsar_config_props (outlink=0x96c8f80) at
 libavfilter/vf_aspect.c:215
 #5  0x00000000005c60a6 in avfilter_config_links (filter=0x96c8bc0) at
 libavfilter/avfilter.c:318
 #6  0x00000000005c604c in avfilter_config_links (filter=0x96c9140) at
 libavfilter/avfilter.c:307
 #7  0x00000000005c604c in avfilter_config_links (filter=0x96c8900) at
 libavfilter/avfilter.c:307
 #8  0x00000000005d8a02 in graph_config_links (graph=<optimized out>,
 log_ctx=<optimized out>)
     at libavfilter/avfiltergraph.c:261
 #9  avfilter_graph_config (graphctx=<optimized out>, log_ctx=0x0) at
 libavfilter/avfiltergraph.c:1279
 #10 0x000000000046a53f in configure_filtergraph (fg=<optimized out>) at
 fftools/ffmpeg_filter.c:1109
 #11 0x00000000004cad35 in ifilter_send_frame (ifilter=<optimized out>,
 frame=<optimized out>)
     at fftools/ffmpeg.c:2179
 #12 send_frame_to_filters (ist=0x93cae00, decoded_frame=0x96c17c0) at
 fftools/ffmpeg.c:2260
 #13 0x00000000004a07dc in decode_video (ist=<optimized out>,
 pkt=<optimized out>, got_output=<optimized out>,
     duration_pts=<optimized out>, eof=<optimized out>,
 decode_failed=<optimized out>) at fftools/ffmpeg.c:2459
 #14 process_input_packet (ist=<optimized out>, pkt=<optimized out>,
 no_eof=<optimized out>)
     at fftools/ffmpeg.c:2613
 #15 0x00000000004ba058 in process_input (file_index=0) at
 fftools/ffmpeg.c:4303
 #16 0x000000000048d60b in transcode_step () at fftools/ffmpeg.c:4628
 #17 transcode () at fftools/ffmpeg.c:4682
 #18 0x0000000000487dc4 in main (argc=10, argv=<optimized out>) at
 fftools/ffmpeg.c:4884
 (gdb) c
 Continuing.
 libavfilter/vf_aspect.c:81:62: runtime error: signed integer overflow:
 1022679769 * 17 cannot be represented in type 'int'
 }}}
 Please confirm.
 Thanks

--
Ticket URL: <https://trac.ffmpeg.org/ticket/8323>
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