There is likely a better way to fix this, this is mainly to show the problem

Fixes: MC within same frame resulting in overlapping memcpy()
Fixes: 60189/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HEVC_fuzzer-4992746590175232
Fixes: 61753/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HEVC_fuzzer-5022150806077440
Fixes: 58062/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HEVC_fuzzer-4717458841010176

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

These casts cast const away temporarily; they are safe, because
the pointers that are initialized point to const data. But this
is nevertheless not nice and leads to warnings when using
-Wcast-qual. blend_modes.c generates 546 (2*39*7) such warnings
which is the majority of such warnings for FFmpeg as a whole.
vf_blend.c and vf_blend_init.h also use this pattern;
they have also been changed.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

lzma_stream.next_in is const for more than 15 years now
and has been so in every release of liblzma.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

The const makes no sense and is later cast away.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Forgotten in 27f8c9b2.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Forgotten in 27f8c9b2.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Only the latter is valid ISO C.
Reviewed-by: James Almer <jamrial@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Forgotten in 30e1e7e0.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

It is not necessary at all. So remove it.
This also breaks an inclusion cycle mem.h->avutil.h->common.h->mem.h.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Up until now, avutil.h includes common.h which includes mem.h which
includes avutil.h, so that all these headers are in fact equivalent.
Yet mem.h does not need to include avutil.h at all and when it no longer
does, including common.h will no longer include error.h (included by
avutil.h) as well; change this by moving error.h to avutil.h, as error.h
is clearly a commonly used header.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Most users of ffio_init_context() simply want to wrap
a buffer into an AVIOContext; they do not provide
function pointers at all.

Therefore this commit adds shortcuts for these two common
operations. This also allows to accept const data when reading
(i.e. the const is now cast away at a central place in
ffio_init_read_context() instead of at several callers).
This also allows to constify the data in ff_text_init_buf().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

These defines are also used in other contexts than just AVCodecContext
ones, e.g. in libavformat. Furthermore, given that these defines are
public, the AV-prefix is the right one, so deprecate (and not just move)
the FF-macros.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

AVCodec is only ever used as an incomplete type (i.e. via a pointer
to an AVCodec) in avformat.h and it is not really part of the core
of avformat.h or libavformat; almost none of our internal users
make use of it (and none make use of hwcontext.h, which is implicitly
included). So switch to use struct AVCodec, but continue to include
codec.h for external users for compatibility.

Also, do the same for AVFrame and frame.h, which is implicitly included
by codec.h (via lavu/hwcontext.h).

Also, remove an unnecessary inclusion of <time.h>.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Namely, out of matroska_parse_tracks().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

and also perform the remainder of the subtitle parsing directly
after mkv_parse_subtitle_codec().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Out of matroska_parse_tracks(), that is.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Namely to a place after the AVStream has already been created,
so that it can be directly attached to it.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

More exactly, factor codec-specific video parsing out of
matroska_parse_tracks(). This is intended to improve readability.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Also fix a variable shadowing.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

If the size of the data of an EbmlBin is > 0, its data is always
present, as ebml_read_binary() always leaves the buffer
in a consistent state (even on error).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

More exactly, factor codec-specific audio parsing out of
matroska_parse_tracks(). This is intended to improve readability.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

This is in preparation for future commits.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

Up until now, matroska_parse_tracks() has two main ways
to set AVCodecParameters.extradata: A generic way via CodecPrivate
(possibly with an offset) and by allocating a buffer manually;
the pointer to this buffer is stored in a stack pointer.

In particular, the latter method is problematic, as the buffer
needs to be freed manually in case of error (currently there
are no error conditions between the place where it is set
to AVCodecParameters.extradata).

Most of these buffers are very small (<= 22B), so replace
the pointer to an allocated buffer with a stack buffer
and set the extradata directly for the one place where
the buffer may not be small.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>