Fixes: out of array access
Fixes: 27424/clusterfuzz-testcase-minimized-ffmpeg_dem_VIVIDAS_fuzzer-5682070692823040
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The cropdetect filter, at present, skips the first two frames. This
behaviour is hardcoded.
New option 'skip' allows users to change this. Convenient for when
input is a single image or a trimmed video stream.
Default is kept at 2 to preserve current behaviour.
Monochrome encoding with libaom was buggy for a long time, but this was
finally sorted out in libaom 2.0.1 (2.0.0 is almost there but was still
buggy in realtime mode).
We'll keep support for libaom 1.x around until the LTS distros that
include it are EOL (which is still a long time from now).
Fixes: https://trac.ffmpeg.org/ticket/7599
Do this by converting big-endian side data to little endian for
checksumming.
Reviewed-by: Andriy Gelman <andriy.gelman@gmail.com>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Nothing guarantees that the size of side data containing a palette
is actually divisible by four (although it should be); but for
big-endian systems, an algorithm is used that presupposed this.
So switch to an algorithm that does not overread: It processes
four bytes at a time, but only if all of them are contained in
the side data.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
By switching from ff_init_vlc_sparse() to ff_init_vlc_from_lengths() one
can replace a table of codes of type uint16_t by a table of symbols of
type uint8_t, saving space.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Commit 1a29804558 guarded several
initializations of static data in the AAC decoders with an AVOnce and
set the FF_CODEC_CAP_INIT_THREADSAFE flag, believing the former to be
sufficient for the latter. It wasn't, because several of these static
tables are shared with other components, so that there might be data
races if they are initialized from multiple threads. This affected
initializing the ff_sine_* tables as well as initializing the
ff_aac_pow*sf_tab tables (shared between both decoders and encoder) as
well as ff_aac_kbd_* tables (shared between encoder and floating point
decoder).
Commit 3d62e7a30f set the
FF_CODEC_CAP_INIT_THREADSAFE flag for the AAC encoder. More explicitly,
this commit used the same AVOnce to guard initializing ff_aac_pow*sf_tab
in the encoder and to guard initializing the static data of each
decoder; the ensuing catastrophe was "fixed" in commit
ec0719264c by using a single AVOnce
for each codec again. But the codec cap has not been removed and
therefore the encoder claimed to be init-threadsafe, but wasn't, because
of the same tables as above.
The ff_sine_* tables as well as ff_aac_pow*sf_tab tables have already
been fixed; this commit deals with the ff_aac_kbd_* tables, making the
encoder as well as the floating-point decoder init-threadsafe (the
fixed-point decoder is it already).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The floating point kbd tables for 120 and 960 samples are only used by
the floating point decoder whereas the fixed point kbd tables for 128
and 1024 samples are only used by the fixed point AAC decoder. So move
these tables to their only users. This ensures that they are not
accidentally used somewhere else without ensuring that initializing
these tables stays thread-safe (as it is now because the only place from
where they are initialized is guarded by an AVOnce).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The floating point AAC decoder is the only user of these tables, so it
makes sense to move them there. Furthermore, initializing the ordinary
power-of-two sinetables is currently not thread-safe and if the 120- and
960-point sinetables were not moved, one would have to choose whether
to guard initializing these two tables with their own AVOnces or not.
Doing so would add unnecessary AVOnces as the AAC decoder already guards
initializing its static data by an AVOnce; not doing so would be fragile
if a second user of these tables were to be added.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
There are no ff_sine_windows for 2^i, 0 <= i < 5, so one should check
for the index being >= 5.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Both the fixed as well as the floating point mpegaudio decoders use
LUTs of type int8_t and uint32_t with 32K entries each; these tables
are completely the same, yet they are not shared. This commit makes
them shared. When both fixed as well as floating point decoders are
enabled, this saves 160KiB from the bss segment for a normal build
(translating into 160KiB less memory usage if both a shared as well as
a floating point decoder have actually been used) and 160KiB from the
binary for a build with hardcoded tables.
It also means that the code to create said LUTs is no longer duplicated
(for a normal build).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The csa_tables (which always consist of 32 entries of four byte each,
but the type depends upon whether the decoder is fixed or
floating-point) are currently initialized once during decoder
initialization; yet it turns out that this is actually no benefit: The
code used to initialize these tables takes up 153 (fixed point) and 122
(floating point) bytes when compiled with GCC 9.3 with -O3 on x64, so it
is better to just hardcode these tables.
Essentially the same applies to the is_tables: They have a size of 128B
each and the code to initialize them occupies 149 (fixed point) resp.
140 (floating point) bytes. So hardcode them, too.
To make the origin of the tables clear, references to the code used to
create them have been added.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Each invocation of this function is only entered once, so using a static
array makes no sense (and given that the whole array is reinitialized at
the beginning of this function, it wouldn't even make sense if the
function were called multiple times).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The mpegaudio_tablegen header contains code to initialize several
tables; it is included in both the fixed as well as the floating point
mpegaudio decoders and some of these tables are only used by the fixed
resp. floating point decoders; yet both types are always initialized,
leaving the compiler to figure out that one of them is unused.
GCC 9.3 fails at this (even with -O3):
$ readelf -s mpegaudiodec_fixed.o|grep _float
28: 0000000000001660 32768 OBJECT LOCAL DEFAULT 4 expval_table_float
An actually unused table (expval_table_fixed/float) of size 32KiB is kept
and initialized (the reason for this is probably that this table is read
from, namely to initialize another table: exp_table_fixed/float; of course
the float resp. fixed tables are not used in the fixed resp. floating point
decoder).
Therefore #ifdef the unneeded tables away.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Up until now, there were several indiviual tables which were accessed
via pointers to them; by combining the tables, one can avoid said
pointers, saving space.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
By switching from ff_init_vlc_sparse() to ff_init_vlc_from_lengths() one
can replace tables of codes of type uint16_t by tables of symbols of
type uint8_t; this saves about 1.3KB for both the fixed and floating
point decoders (if enabled).
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
By switching from ff_init_vlc_sparse() to ff_init_vlc_from_lengths() one
can remove the array of codes of type uint16_t here; given that the
symbols are the default ones (0,1,2,...), no explicit symbols table
needs to be added.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
By switching from ff_init_vlc_sparse() to ff_init_vlc_from_lengths() one
can remove arrays of codes in cases where there were already symbols
tables.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Expressions like array[get_vlc2()] can be optimized by using a symbols
table if the array is always the same for a given VLC. This requirement
is fulfilled for several VLCs used by the AAC decoders.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Michael Niedermayer
James Almer
Mark Reid
Gyan Doshi
Philip Langdale
Andreas Rheinhardt