Fixes#1053 / CVE-2018-5727
Note: I don't consider this issue to be a security vulnerability, in
practice.
At least with gcc or clang compilers on x86_64 which generate the same
assembly code with or without that fix.
width/length dimensions read from bmp headers are not necessarily
valid. For instance they may have been maliciously set to very large
values with the intention to cause DoS (large memory allocation, stack
overflow). In these cases we want to detect the invalid size as early
as possible.
This commit introduces a counter which verifies that the number of
written bytes corresponds to the advertized width/length.
Fixes#1059 (CVE-2018-6616).
When compressing a lot of slices (starting from 44 FullHD slices with 3 8bit components in our experiments) the rate values are high enough to cause an int overflow that leads to negative lengths and wrong results. The cast happens too late.
Tile components in a JP2 image might have null data pointer by defining a
zero component size (for example using large horizontal or vertical
sampling periods). This null data pointer leads to null image component
data pointer, causing crash when dereferenced without != null check in
imagetopnm.
Add != null check.
This commit addresses #1152 (CVE-2018-18088).
* Fix some potential overflow issues
Put sizeof to the beginning of the multiplication to enforce that
size_t instead of smaller integer types is used for the calculation.
This fixes warnings from LGTM:
Multiplication result may overflow 'unsigned int'
before it is converted to 'unsigned long'.
It also allows removing some type casts.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
* Fix code indentation
Signed-off-by: Stefan Weil <sw@weilnetz.de>
This uses snprintf() with correct buffer length instead of sprintf(), which
prevents a buffer overflow when providing a long output prefix. Furthermore
the program exits with an error when the provided output prefix is too long.
Fixes#1088.
In the case where a BMP file declares compression 3 (BI_BITFIELDS)
with header size <= 56, all bitmask values keep their initialization
value 0. This may lead to various undefined behavior later e.g. when
doing 1 << (l_comp->prec - 1).
This issue does not affect files with bit count 16 because of a check
added in 16240e2 which sets default values to the color masks if they
are all 0.
This commit adds similar checks for the 32 bit case.
Also, if a BMP file declares compression 3 with header size >= 56 and
intentional 0 bitmasks, the same issue will be triggered in both the
16 and 32 bit count case.
This commit adds checks to bmp_read_info_header() rejecting BMP files
with "intentional" 0 bitmasks. These checks might be removed in the
future when proper handling of zero bitmasks will be available in
openjpeg2.
fixes#1057 (CVE-2018-5785)