mirror of
https://github.com/rd-stuffs/msm-4.14.git
synced 2025-02-20 11:45:48 +08:00
d2b33d0a14
[ Upstream commit a08b8f8557ad88ffdff8905e5da972afe52e3307 ]
This is an effort to get rid of all multiplications from allocation
functions in order to prevent integer overflows [1][2].
As the "ff" variable is a pointer to "struct ff_device" and this
structure ends in a flexible array:
struct ff_device {
[...]
struct file *effect_owners[] __counted_by(max_effects);
};
the preferred way in the kernel is to use the struct_size() helper to
do the arithmetic instead of the calculation "size + count * size" in
the kzalloc() function.
The struct_size() helper returns SIZE_MAX on overflow. So, refactor
the comparison to take advantage of this.
This way, the code is more readable and safer.
This code was detected with the help of Coccinelle, and audited and
modified manually.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
Link: https://github.com/KSPP/linux/issues/160 [2]
Signed-off-by: Erick Archer <erick.archer@outlook.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/AS8PR02MB72371E646714BAE2E51A6A378B152@AS8PR02MB7237.eurprd02.prod.outlook.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit e52cfcf68df0b52565be68106e9f65ab8077b48a)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.