[Ffmpeg-devel] valgrind jump on uninitialised value in mpa_decode_header

[Michael Niedermayer]

Hi

On Thu, Sep 14, 2006 at 04:48:12PM +0200, Baptiste Coudurier wrote:
> Hi
> 
> On current svn, it seams valgrind complains about:
> 
> ==7783== Conditional jump or move depends on uninitialised value(s)
> ==7783==    at 0x81CBF42: decode_header (mpegaudiodec.c:1223)
> ==7783==    by 0x81CDEDA: mpa_decode_header (mpegaudiodec.c:1273)
> ==7783==    by 0x80A281F: mp3_read_probe (mp3.c:268)
> ==7783==    by 0x8070077: av_open_input_file (utils.c:433)
> ==7783==    by 0x805EDFC: opt_input_file (ffmpeg.c:2904)
> ==7783==    by 0x8068395: parse_options (cmdutils.c:99)
> ==7783==    by 0x8065297: main (ffmpeg.c:4336)
> 
> which corresponds to:
> 
> /* if no frame size computed, signal it */
> if (!s->free_format_frame_size)
>    return 1;
> 
> Indeed, s is passed as argument and declared as:
> MPADecodeContext s1, *s = &s1; and is not initialized.
> 
> Is that potentially harmful ?

yes, feel free to assume free_format_frame_size=0 and simplify the
code

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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