commit ba9cf6b430433e57bfc8072364e944b7c0eca2a4 upstream.
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: cea28e7a55e7 ("media: pulse8-cec: reorganize function order")
Cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
