This prevents part of one exploit leading to an information leak
Found-by: Emil Lerner and Pavel Cheremushkin
Reported-by: Thierry Foucu <tfoucu@google.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Some muxers may use the BMP_HEADER Format Data size instead
of the ASF-specific one.
Bug-Id: 1020
CC: libav-stable@libav.org
Signed-off-by: Diego Biurrun <diego@biurrun.de>
Fixes pts gaps when reading AVI files > 256GiB generated by FFmpeg.
Signed-off-by: Tobias Rapp <t.rapp@noa-archive.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
It is supposed to be a flag. The only currently defined value is
AVIO_SEEKABLE_NORMAL, but other ones may be added in the future.
However all the current lavf code treats this field as a bool (mainly
for historical reasons).
Change all those cases to properly check for AVIO_SEEKABLE_NORMAL.
This assert can with crafted files fail, a warning is already printed
for this case.
Fixes assertion failure
Fixes:1/assert.avi
Found-by: 连一汉 <lianyihan@360.cn>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Currently, AVStream contains an embedded AVCodecContext instance, which
is used by demuxers to export stream parameters to the caller and by
muxers to receive stream parameters from the caller. It is also used
internally as the codec context that is passed to parsers.
In addition, it is also widely used by the callers as the decoding (when
demuxer) or encoding (when muxing) context, though this has been
officially discouraged since Libav 11.
There are multiple important problems with this approach:
- the fields in AVCodecContext are in general one of
* stream parameters
* codec options
* codec state
However, it's not clear which ones are which. It is consequently
unclear which fields are a demuxer allowed to set or a muxer allowed to
read. This leads to erratic behaviour depending on whether decoding or
encoding is being performed or not (and whether it uses the AVStream
embedded codec context).
- various synchronization issues arising from the fact that the same
context is used by several different APIs (muxers/demuxers,
parsers, bitstream filters and encoders/decoders) simultaneously, with
there being no clear rules for who can modify what and the different
processes being typically delayed with respect to each other.
- avformat_find_stream_info() making it necessary to support opening
and closing a single codec context multiple times, thus
complicating the semantics of freeing various allocated objects in the
codec context.
Those problems are resolved by replacing the AVStream embedded codec
context with a newly added AVCodecParameters instance, which stores only
the stream parameters exported by the demuxers or read by the muxers.
If max in clean_index is set to a negative ast->sample_size, the
following loop never ends:
while (max < 1024)
max += max;
Thus set ast->sample_size to 0 if it would otherwise be negative.
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
If bit_rate is negative, it can trigger an av_assert2 in av_rescale_rnd.
Since av_rescale returns int64_t, but st->codec_bit_rate is int, it can
also overflow into a negative value.
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>