[PATCH 6/7] lib/random32.c: Randomize timeout to the millisecond, not the second

George Spelvin
2014-06-07T08:29:01Z

If you're going to bother randomizing it, do it right.
And use prandom_u32_max(), which is designed for the job, rather
than "% 40".

Signed-off-by: George Spelvin <linux@horizon.com>
---
lib/random32.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/random32.c b/lib/random32.c
index eee60100..9cc410dd 100644
--- a/lib/random32.c
+++ b/lib/random32.c
@@ -208,14 +208,14 @@ static DEFINE_TIMER(seed_timer, __prandom_timer, 0, 0);
static void __prandom_timer(unsigned long dontcare)
{
u32 entropy;
- unsigned long expires;
+ unsigned int expires;

get_random_bytes(&entropy, sizeof(entropy));
prandom_seed(entropy);

/* reseed every ~60 seconds, in [40 .. 80) interval with slack */
- expires = 40 + (prandom_u32() % 40);
- seed_timer.expires = jiffies + msecs_to_jiffies(expires * MSEC_PER_SEC);
+ expires = 40000 + prandom_u32_max(40000);
+ seed_timer.expires = jiffies + msecs_to_jiffies(expires);

add_timer(&seed_timer);
}
--
2.0.0