This is required by the APNG spec
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit a1736926e9)
Conflicts:
libavcodec/pngdec.c
Multiple IHDR chunks are forbidden in PNG
Fixes inconsistency and out of array accesses
Fixes: asan_heap-oob_4d5c5a_1738_cov_2638287726_c-m2-8f2b481b7fd9bd745e620b7c01a18df2.png
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 47f4e2d896)
Conflicts:
libavcodec/pngdec.c
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
AV_PIX_FMT_MONOBLACK has the AV_PIX_FMT_FLAG_BITSTREAM flag, i.e.
linesize can be smaller than width.
Since x_offset is only check against the width, this can lead to
x_offset * bpp >= image_linesize.
In this case ptr could be set to a position outside the image_buf in
png_handle_row, leading to memory corruption and thus crashes.
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 372aa0777a)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
During the loop ret can get changed. Since it is not set on all failure
paths, decode_frame_common can return 0 even though an error occurred.
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 8f760be4d3)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This check was removed in commit 08aec6f6, but
s->last_picture.f->data[0] is still used in handle_p_frame_apng
unconditionally.
This fixes a segmentation fault.
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 287dbb0771)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Use 'if (CONFIG_APNG_DECODER)' where needed, so that the compiler can
optimize out some portion of code.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
There is no need to memset the zlib output buffer, as there is no
blending happening there. Instead, do not blend when the dispose
operation is set to 'background' (tranparent black).
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Fixes out of array read
Fixes: asan_heap-oob_20b0a06_1962_cov_1907976991_delete_node_small.png
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Fixes out of array access
Fixes: asan_heap-oob_20a6c26_2690_cov_3434532168_mail.png
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Fixes out of array accesses
Fixes: asan_heap-oob_14dbfcf_4_asan_heap-oob_1ce5767_179_add_method_small.png
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
The rationale is that you have a packed format in form
<greyscale sample> <alpha sample> <greyscale sample> <alpha sample>
and shortening greyscale to 'G' might make one thing about Greenscale instead.
An alias pixel format and color space name are provided for compatibility.
If the input buffer contains more data after the deflate stream,
the loop previously left running infinitely, with inflate returning
Z_STREAM_END.
Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
Signed-off-by: Martin Storsjö <martin@martin.st>