[ 44/76] timekeeping: Cast raw_interval to u64 to avoid shift overflow

Greg Kroah-Hartman
2012-10-19T02:59:42Z

From: Dan Carpenter <dan.carpenter@oracle.com>

commit 5b3900cd409466c0070b234d941650685ad0c791 upstream.

We fixed a bunch of integer overflows in timekeeping code during the 3.6
cycle. I did an audit based on that and found this potential overflow.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Link: http://lkml.kernel.org/r/20121009071823.GA19159@elgon.mountain
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
kernel/time/timekeeping.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1111,7 +1111,7 @@ static cycle_t logarithmic_accumulation(
accumulate_nsecs_to_secs(tk);

/* Accumulate raw time */
- raw_nsecs = tk->raw_interval << shift;
+ raw_nsecs = (u64)tk->raw_interval << shift;
raw_nsecs += tk->raw_time.tv_nsec;
if (raw_nsecs >= NSEC_PER_SEC) {
u64 raw_secs = raw_nsecs;