Re: [PATCH v4 11/13] net/route: use get_random_int for random counter

[Theodore Ts'o]

On Tue, Jun 06, 2017 at 07:48:02PM +0200, Jason A. Donenfeld wrote:
> Using get_random_int here is faster, more fitting of the use case, and
> just as cryptographically secure. It also has the benefit of providing
> better randomness at early boot, which is when many of these structures
> are assigned.
> 
> Also, semantically, it's not really proper to have been assigning an
> atomic_t in this way before, even if in practice it works fine.
> 
> Signed-off-by: Jason A. Donenfeld 
> Cc: David Miller 

Applied to the dev branch of the random.git branch, thanks.

- Ted

[PATCH v4 11/13] net/route: use get_random_int for random counter

[Jason A. Donenfeld]

Using get_random_int here is faster, more fitting of the use case, and
just as cryptographically secure. It also has the benefit of providing
better randomness at early boot, which is when many of these structures
are assigned.

Also, semantically, it's not really proper to have been assigning an
atomic_t in this way before, even if in practice it works fine.

Signed-off-by: Jason A. Donenfeld 
Cc: David Miller 
---
 net/ipv4/route.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 655d9eebe43e..11e001a42094 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2936,8 +2936,7 @@ static __net_init int rt_genid_init(struct net *net)
 {
atomic_set(>ipv4.rt_genid, 0);
atomic_set(>fnhe_genid, 0);
-   get_random_bytes(>ipv4.dev_addr_genid,
-sizeof(net->ipv4.dev_addr_genid));
+   atomic_set(>ipv4.dev_addr_genid, get_random_int());
return 0;
 }
 
-- 
2.13.0