iff: crash with prepared file

[ami_stuff]

Attached file is a modified IFF RGBN to be recognized as IFF PBM.

(gdb) r -i crash.iff out.bmp
Starting program: d:\mingw\msys\1.0\ffmpeg\ffmpeg_g.exe -i crash.iff out.b
mp
[New Thread 2604.0x6dc]
ffmpeg version 0.9.1.git Copyright (c) 2000-2012 the FFmpeg developers
  built on Mar 10 2012 16:15:15 with gcc 4.6.1
  configuration: --disable-yasm --disable-ffprobe
  libavutil      51. 42.100 / 51. 42.100
  libavcodec     54. 10.100 / 54. 10.100
  libavformat    54.  2.100 / 54.  2.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 63.100 /  2. 63.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  7.100 /  0.  7.100
[IFF @ 03862340] Estimating duration from bitrate, this may be inaccurate
Input #0, IFF, from 'crash.iff':
  Duration: N/A, bitrate: N/A
    Stream #0:0: Video: iff_byterun1 (PBM  / 0x204D4250), rgba, 1024x768, SAR 1:
1 DAR 4:3, 90k tbr, 90k tbn, 90k tbc
Incompatible pixel format 'rgba' for codec 'bmp', auto-selecting format 'bgra'
[image2 @ 03863320] Frame rate very high for a muxer not effciciently supporting
 it.
Please consider specifiying a lower framerate, a different muxer or -vsync 2
[buffer @ 03871e40] w:1024 h:768 pixfmt:rgba tb:1/1000000 sar:1/1 sws_param:
[buffersink @ 038713e0] auto-inserting filter 'auto-inserted scale 0' between th
e filter 'src' and the filter 'out'
[scale @ 03871800] w:1024 h:768 fmt:rgba -> w:1024 h:768 fmt:bgra flags:0x4
Output #0, image2, to 'out.bmp':
  Metadata:
    encoder         : Lavf54.2.100
    Stream #0:0: Video: bmp, bgra, 1024x768 [SAR 1:1 DAR 4:3], q=2-31, 200 kb/s,
 90k tbn, 90k tbc
Stream mapping:
  Stream #0:0 -> #0:0 (iff_byterun1 -> bmp)
Press [q] to stop, [?] for help

Program received signal SIGSEGV, Segmentation fault.
0x006e8857 in decode_byterun (buf_end=0x3f80346 "",
    buf=0x3ec0043 "\021C\021C#C\021\063\024C\023C#C\021C#T%d1e1T\"e7T \fC!T\"T1T
\"T2T'e1d#T$e1d1d!T!d!T#d\"T    S!T\"d1T \bd\"e2u3vBv1ć2ćAć1vAv1u1e1vAe1U1T!T4T#
T1d1e0  uAvAćQ\230q¦\241-+ŢĎŢŃţňŢĐT-ęĺ\230é\230rŚcçQćQćAvAćCvBuAu2e1d\"e1u1vAćBu
3ćCć1ćAľBů4ć1ů1u2uAu1ů1ć"..., dst_size=1024, dst=0x0) at libavcodec/iff.c:443
443                 memcpy(dst + x, buf, FFMIN3(length, dst_size - x, buf_end -
buf));
(gdb) bt
#0  0x006e8857 in decode_byterun (buf_end=0x3f80346 "",
    buf=0x3ec0043 "\021C\021C#C\021\063\024C\023C#C\021C#T%d1e1T\"e7T \fC!T\"T1T
\"T2T'e1d#T$e1d1d!T!d!T#d\"T    S!T\"d1T \bd\"e2u3vBv1ć2ćAć1vAv1u1e1vAe1U1T!T4T#
T1d1e0  uAvAćQ\230q¦\241-+ŢĎŢŃţňŢĐT-ęĺ\230é\230rŚcçQćQćAvAćCvBuAu2e1d\"e1u1vAćBu
3ćCć1ćAľBů4ć1ů1u2uAu1ů1ć"..., dst_size=1024, dst=0x0) at libavcodec/iff.c:443
#1  decode_frame_byterun1 (avctx=0x3dd0920, data=0x3872ca0,
    data_size=0x22de20, avpkt=0x22dbc8) at libavcodec/iff.c:641
#2  0x004f9770 in avcodec_decode_video2 (avctx=0x3dd0920, picture=0x3872ca0,
    got_picture_ptr=0x22de20, avpkt=0x22dd30) at libavcodec/utils.c:1351
#3  0x004069cb in transcode_video (pkt_pts=<optimized out>,
    got_output=<optimized out>, pkt=<optimized out>, ist=<optimized out>)
    at ffmpeg.c:2102
#4  output_packet (ist=0x38718e0, ost_table=0x386fce0, nb_ostreams=1,
    pkt=0x22fb28) at ffmpeg.c:2270
#5  0x0040bf3b in transcode (output_files=0x3871d60, nb_output_files=1,
    input_files=0x38719a0, nb_input_files=1) at ffmpeg.c:3082
#6  0x0022ff48 in ?? ()
Backtrace stopped: Not enough registers or memory available to unwind further
(gdb)

[Carl Eugen Hoyos]

Fixed by Peter Ross.