[ 032/105] timekeeping: Cast raw_interval to u64 to avoid shift overflow

[Ben Hutchings]

3.2-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

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@xxxxxxxxxx>
Acked-by: John Stultz <johnstul@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20121009071823.GA19159@xxxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
[bwh: Backported to 3.2: adjust context; use timekeeper.raw_interval]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 kernel/time/timekeeping.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -992,7 +992,7 @@ static cycle_t logarithmic_accumulation(
 	}
 
 	/* Accumulate raw time */
-	raw_nsecs = timekeeper.raw_interval << shift;
+	raw_nsecs = (u64)timekeeper.raw_interval << shift;
 	raw_nsecs += raw_time.tv_nsec;
 	if (raw_nsecs >= NSEC_PER_SEC) {
 		u64 raw_secs = raw_nsecs;


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