The data of an AVPacket may be a part of the data of an AVBufferRef;
Therefore av_grow_packet() doesn't reallocate if the available space in
the actual buffer is sufficient for the enlargement. But given that it
also zeroes the padding it also needs to make sure that the buffer is
actually writable; this commit implements this.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The documentation of av_dict_set() states that values >= 0 indicate
success, whereas av_packet_unpack_dictionary() implies that return
values > 0 are impossible. So only forward the return value of
av_dict_set() in av_packet_unpack_dictionary() on error.
(Btw: av_dict_set() does currently not return values > 0.)
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Up until now, it was completely unspecified what the content of the
destination packet dst was on error. Depending upon where the error
happened calling av_packet_unref() on dst might be dangerous.
This commit changes this by making sure that dst is blank on error, so
unreferencing it again is safe (and still pointless). This behaviour is
documented.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
av_packet_ref() mostly treated the destination packet dst as uninitialized,
i.e. the destination fields were simply overwritten. But if the source
packet was not reference-counted, dst->buf was treated as if it pointed
to an already allocated buffer (if != NULL) to be reallocated to the
desired size.
The documentation did not explicitly state whether the dst will be treated
as uninitialized, but it stated that if the source packet is not refcounted,
a new buffer in dst will be allocated. This and the fact that the side-data
as well as the codepath taken in case src is refcounted always treated the
packet as uninitialized means that dst should always be treated as
uninitialized for the sake of consistency. And this behaviour has been
explicitly documented.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
av_mallocz + av_init_packet leads to the same result as av_mallocz +
av_packet_unref, but faster.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
It works as a drop in replacement for the deprecated av_dup_packet(),
to ensure a packet is reference counted.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
Zero sized packets are already handled below in the function.
This is more in line with av_packet_ref().
Signed-off-by: James Almer <jamrial@gmail.com>
This effectively copies the side data elements from src instead of
potentially merging them with those already existing in dst.
This by extension also removes the only dependency on existing values
in the dst packet.
Reviewed-by: wm4 <nfxjfg@googlemail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
This avoids scaning beyond what a valid packet can contain
Fixes: Timeout
Fixes: 541/clusterfuzz-testcase-610189291657625
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
It was never meant to do otherwise, as av_packet_get_side_data() returns the first
entry it finds of a given type.
Based on code from libavformat's av_stream_add_side_data().
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
Fixes: 1293/clusterfuzz-testcase-minimized-6054752074858496
See: [FFmpeg-devel] [PATCH] avcodec/avcodec: Limit the number of side data elements per packet
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This patch deprecates anything that has to do with merging/splitting
side data. Automatic side data merging (and splitting), as well as all
API symbols involved in it, are removed completely.
Two FF_API_ defines are dedicated to deprecating API symbols related to
this: FF_API_MERGE_SD_API removes av_packet_split/merge_side_data in
libavcodec, and FF_API_LAVF_KEEPSIDE_FLAG deprecates
AVFMT_FLAG_KEEP_SIDE_DATA in libavformat.
Since it was claimed that changing the default from merging side data to
not doing it is an ABI change, there are two additional FF_API_ defines,
which stop using the side data merging/splitting by default (and remove
any code in avformat/avcodec doing this): FF_API_MERGE_SD in libavcodec,
and FF_API_LAVF_MERGE_SD in libavformat.
It is very much intended that FF_API_MERGE_SD and FF_API_LAVF_MERGE_SD
are quickly defined to 0 in the next ABI bump, while the API symbols are
retained for a longer time for the sake of compatibility.
AVFMT_FLAG_KEEP_SIDE_DATA will (very much intentionally) do nothing for
most of the time it will still be defined. Keep in mind that no code
exists that actually tries to unset this flag for any reason, nor does
such code need to exist. Code setting this flag explicitly will work as
before. Thus it's ok for AVFMT_FLAG_KEEP_SIDE_DATA to do nothing once
side data merging has been removed from libavformat.
In order to avoid that anyone in the future does this incorrectly, here
is a small guide how to update the internal code on bumps:
- next ABI bump (probably soon):
- define FF_API_LAVF_MERGE_SD to 0, and remove all code covered by it
- define FF_API_MERGE_SD to 0, and remove all code covered by it
- next API bump (typically two years in the future or so):
- define FF_API_LAVF_KEEPSIDE_FLAG to 0, and remove all code covered
by it
- define FF_API_MERGE_SD_API to 0, and remove all code covered by it
This forces anyone who actually wants packet side data to temporarily
use deprecated API to get it all. If you ask me, this is batshit fucked
up crazy, but it's how we roll. Making AVFMT_FLAG_KEEP_SIDE_DATA to be
set by default was rejected as an ABI change, so I'm going all the way
to get rid of this once and for all.
Reviewed-by: James Almer <jamrial@gmail.com>
Reviewed-by: Rostislav Pehlivanov <atomnuker@gmail.com>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Reflects the actual code and silences a gcc warning:
libavcodec/utils.c:2102:36: warning: passing argument 1 of 'av_packet_get_side_data' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
If realloc fails, the pointer is overwritten and the previously allocated
buffer is leaked, which goes against the expected behavior of keeping the
packet unchanged in case of error.
Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
* commit '8996515b137f962e3a8691241c285c96437b6c53':
avpacket: fix setting AVPacket.data in av_packet_ref()
This commit is a noop, see ed3a02547c
Merged-by: Clément Bœsch <u@pkh.me>
This mimics the behaviour of other av_*_new_side_data().
This is not caught by the malloc check, since padding
is always added to the allocated size.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Fixes out of array read
Fixes: mozilla bug 1266129
Found-by: Tyson Smith
Tested-by: Tyson Smith
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Some containers, like webm/mkv, will contain this mastering metadata.
This is analogous to the way 3D fpa data is handled (in frame and
packet side data).
Signed-off-by: Neil Birkbeck <neil.birkbeck@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This allows to copy information related to the stream ID from the demuxer
to the muxer, thus allowing for example to retain information related to
synchronous and asynchronous KLV data packets. This information is used
in the muxer when remuxing to distinguish the two kind of packets (if the
information is lacking, data packets are considered synchronous).
The fate reference changes are due to the use of
av_packet_merge_side_data(), which increases the size of the output
packet size, since side data is merged into the packet data.
The previous check only caught sizes from -AV_INPUT_BUFFER_PADDING_SIZE
to -1.
This fixes ubsan runtime error: signed integer overflow: 2147483647 + 32
cannot be represented in type 'int'
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
The previous check only caught sizes from -AV_INPUT_BUFFER_PADDING_SIZE
to -1.
This fixes ubsan runtime error: signed integer overflow: 2147483647 + 32
cannot be represented in type 'int'
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
