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ba9cf6b430
As pointed by Coverity, there is a hidden overflow condition there.
As date is signed and u8 is unsigned, doing:
date = (data[0] << 24)
With a value bigger than 07f will make all upper bits of date
0xffffffff. This can be demonstrated with this small code:
<code>
typedef int64_t time64_t;
typedef uint8_t u8;
int main(void)
{
u8 data[] = { 0xde ,0xad , 0xbe, 0xef };
time64_t date;
date = (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3];
printf("Invalid data = 0x%08lx\n", date);
date = ((unsigned)data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3];
printf("Expected data = 0x%08lx\n", date);
return 0;
}
</code>
Fix it by converting the upper bit calculation to unsigned.
Fixes: cea28e7a55 ("media: pulse8-cec: reorganize function order")
Cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
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.