#14 segfault in audio/acodec/acodec.c

[navtej singh]

looks like a NULL pointer dereference in audio/acodec/acodec.

I can provide bad.mp3 if required.

backtrace

gdb python
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This GDB was configured as "i686-pc-linux-gnu"...
Using host libthread_db library "/lib/libthread_db.so.1".
(gdb) set args dump_wav.py /mnt/windows2/Audio/bad.mp3
(gdb) r
Starting program: /usr/bin/python dump_wav.py /mnt/windows2/Audio/bad.mp3
[Thread debugging using libthread_db enabled]
[New Thread -1211943248 (LWP 8359)]
>>> [*]dumpWAV starting

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1211943248 (LWP 8359)]
0xb7c96234 in free () from /lib/libc.so.6
(gdb) bt
#0 0xb7c96234 in free () from /lib/libc.so.6
#1 0xb78bf3d6 in av_free (ptr=0xb7508008) at audio/mem.c:155
#2 0xb78be014 in ACString_Del (str=0xb7c2e0e0) at audio/acodec/acodec.c:177
#3 0xb78be4e0 in AFrameClose (obj=0xb763e8e0) at audio/acodec/acodec.c:399
#4 0xb7e2c66e in PyEval_EvalFrame (f=0x805a63c) at Python/ceval.c:917
#5 0xb7e34182 in fast_function (func=0xb763a684, pp_stack=0xbfc5ef9c, n=1, na=1, nk=0) at Python/ceval.c:3651
#6 0xb7e33f8a in call_function (pp_stack=0xbfc5ef9c, oparg=1) at Python/ceval.c:3589
#7 0xb7e3044f in PyEval_EvalFrame (f=0x809cedc) at Python/ceval.c:2167
#8 0xb7e31ecb in PyEval_EvalCodeEx (co=0xb7bbea60, globals=0xb7c0c824, locals=0xb7c0c824, args=0x0, argcount=0, kws=0x0, kwcount=0, defs=0x0,
defcount=0, closure=0x0) at Python/ceval.c:2741
#9 0xb7e2bfe3 in PyEval_EvalCode (co=0xb7bbea60, globals=0xb7c0c824, locals=0xb7c0c824) at Python/ceval.c:484
#10 0xb7e60968 in run_node (n=0xb7bf3338, filename=0xbfc6106f "dump_wav.py", globals=0xb7c0c824, locals=0xb7c0c824, flags=0xbfc5f210)
at Python/pythonrun.c:1285
#11 0xb7e608c0 in run_err_node (n=0xb7bf3338, filename=0xbfc6106f "dump_wav.py", globals=0xb7c0c824, locals=0xb7c0c824, flags=0xbfc5f210)
at Python/pythonrun.c:1272
#12 0xb7e6085e in PyRun_FileExFlags (fp=0x804a008, filename=0xbfc6106f "dump_wav.py", start=257, globals=0xb7c0c824, locals=0xb7c0c824, closeit=1,
flags=0xbfc5f210) at Python/pythonrun.c:1263
#13 0xb7e5f42a in PyRun_SimpleFileExFlags (fp=0x804a008, filename=0xbfc6106f "dump_wav.py", closeit=1, flags=0xbfc5f210) at Python/pythonrun.c:869
#14 0xb7e5eb99 in PyRun_AnyFileExFlags (fp=0x804a008, filename=0xbfc6106f "dump_wav.py", closeit=1, flags=0xbfc5f210) at Python/pythonrun.c:673
#15 0xb7e694bd in Py_Main (argc=3, argv=0xbfc5f314) at Modules/main.c:493
#16 0x080486ba in main (argc=3, argv=0xbfc5f314) at Modules/python.c:23
(gdb)

dump_wav.py

#! /bin/env python
import sys
import pymedia.audio.acodec as acodec
import pymedia.muxer as muxer
import time, wave, string, os
import gc

global cnt
cnt=0
def dumpWAV( name ):
print ">>> [*]dumpWAV starting"
name1= str.split( name, '.' )
name2= string.join( name1[ : len( name1 )- 1 ] )
dm= muxer.Demuxer( name1[ -1 ].lower() )
dec= None
f= open( name, 'rb' )
snd= None
s= " "
while len( s ):
s= f.read( 20000 )
if len( s ):
frames= dm.parse( s )
for fr in frames:
global cnt
cnt += 1
if cnt < 1263:
continue
if dec== None:
dec= acodec.Decoder( dm.streams[ 0 ] )
r= dec.decode( fr[ 1 ] )
if r and r.data:
if snd== None:
snd= wave.open( name2+ '.wav', 'wb' )
snd.setparams( (r.channels, 2, r.sample_rate, 0, 'NONE','') )
#snd.writeframes( r.data )

print ">>> [*] dumpWAV done"
if __name__=="__main__":
gc.disable()
dumpWAV(sys.argv[1])