timekeeping: fix 32-bit overflow in get_monotonic_boottime

get_monotonic_boottime adds three nanonsecond values stored
in longs, followed by an s64.  If the long values are all
close to 1e9 the first three additions can overflow and
become negative when added to the s64.  Cast the first
value to s64 so that all additions are 64 bit.

Change-Id: Ibb698eaf0354e2093e35362e26613474dd430ecd
Signed-off-by: Colin Cross <ccross@android.com>
Git-commit: 3b2107dfbe90989e7c904766309d1da9aa7def29
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Nirmal Abraham <nabrah@codeaurora.org>
1 file changed