[FFmpeg-trac] #474(avcodec:new): SIG SEV in clear_blocks_sse in ff_h263_decode_mb

FFmpeg trac at avcodec.org
Mon Sep 19 19:59:56 CEST 2011


#474: SIG SEV  in clear_blocks_sse in ff_h263_decode_mb
-----------------------------------+-----------------------------------
             Reporter:  sgarcia    |                    Owner:
                 Type:  defect     |                   Status:  new
             Priority:  important  |                Component:  avcodec
              Version:  git        |               Resolution:
             Keywords:             |               Blocked By:
             Blocking:             |  Reproduced by developer:  0
Analyzed by developer:  0          |
-----------------------------------+-----------------------------------

Comment (by reimar):

 The relevant code is:
 s->dsp.clear_blocks(s->block[0]);
 I can't see a way for that to crash except if the pointer was corrupted or
 the MpegEncContext freed.
 valgrind might be able to help figure it out.
 However your backtrace is broken so I am rather skeptical anyway:
 #0 0x00e81882 in clear_blocks_sse (blocks=0xb36202e0) at
 libavcodec/x86/dsputil_mmx.c:539
 means the program counter is at 0x00e81882
 However according to the disassembly there is no instruction starting
 there:
 0x00e8187f <clear_blocks_sse+47>: movaps %xmm0,0x60(%edx,%eax,1)
 0x00e81884 <clear_blocks_sse+52>: movaps %xmm0,0x70(%edx,%eax,1)

-- 
Ticket URL: <https://avcodec.org/trac/ffmpeg/ticket/474#comment:4>
FFmpeg <http://ffmpeg.org>
FFmpeg issue tracker


More information about the FFmpeg-trac mailing list