[patch] time: cast ->raw_interval to u64 to avoid shift overflow

From: Dan Carpenter
Date: Tue Oct 09 2012 - 03:18:39 EST


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>
---
I'm not super familiar with this code so please review my work
carefully.

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 5ce06a3..1d1ee67 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1113,7 +1113,7 @@ static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset,
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;
--
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