This also fixes several integer overflows by checking each value before
use.
Fixes: 662/clusterfuzz-testcase-4898131432964096
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Failing earlier causes the context to be insufficiently initialized which
can break decoding future frames with threads
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Avoids leaving stale pointers
Fixes: signal_sigabrt_7ffff70eccc9_819_sabtriple.rm with memlimit 536870912
Found-by: Samuel Groß, Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
MpegEncContext based decoders are only fully initialized after the first
ff_thread_get_buffer() call. The RV30/40 decoders may fail before a frame
buffer was requested. ff_mpeg_update_thread_context() fails on half
initialized MpegEncContexts. Since this can only happen before a the
first frame was decoded there is no need to call
ff_mpeg_update_thread_context().
Based on patches by John Stebbins and tested by John Stebbins.
CC: libav-stable@libav.org
The most interesting parts are initialization in ff_MPV_common_init() and
uninitialization in ff_MPV_common_end().
ff_mpeg_unref_picture and ff_thread_release_buffer have additional NULL
checks for Picture.f, because these functions can be called on
uninitialized or partially initialized Pictures.
NULL pointer checks are added to ff_thread_release_buffer() stub function.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Several decoders disable those anyway and they are not measurably faster
on x86. They might be somewhat faster on other platforms due to missing
emu edge SIMD, but the gain is not large enough (and those decoders
relevant enough) to justify the added complexity.
Fixes use of uninitialized memory
Fixes: msan_uninit-mem_7f75e2a55b88_4146_brokenaudio.rmvb
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Allow supporting files for which the image stride is smaller than
the maximum block size + number of subpel mc taps, e.g. a 64x64 VP9
file or a 16x16 VP8 file with -fflags +emu_edge.
This allows supporting files for which the image stride is smaller than
the max. block size + number of subpel mc taps, e.g. a 64x64 VP9 file
or a 16x16 VP8 file with -fflags +emu_edge.
Move some functions from dsputil. The idea is that videodsp contains
functions that are useful for a large and varied set of video decoders.
Currently, it contains emulated_edge_mc() and prefetch().
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Quite often, the original weights are multiple of 512. By prescaling them
by 1/512 when they are computed (once per frame), no intermediate shifting
is needed, and no prescaling on each call either.
The x86 code already used that trick.
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
Michael Niedermayer
Diego Biurrun
Vittorio Giovara
Michael Niedermayer
Janne Grunau
Gabriel Dume
John Stebbins
wm4
Anton Khirnov
Ronald S. Bultje
Ronald S. Bultje
Martin Storsjö
Clément Bœsch
Piotr Bandurski
Christophe Gisquet