Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1660415

[PATCH v5 11/13] net/route: use get_random_int for random counter

From "Jason A. Donenfeld" <Jason@zx2c4.com>
Newsgroups linux.kernel
Subject [PATCH v5 11/13] net/route: use get_random_int for random counter
Date 2017-06-08 01:30 +0200
Message-ID <tPSyK-4M5-41@gated-at.bofh.it> (permalink)
References <tPSyJ-4M5-7@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


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 <Jason@zx2c4.com>
Cc: David Miller <davem@davemloft.net>
---
 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 6883b3d4ba8f..32a3332ec9cf 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2944,8 +2944,7 @@ static __net_init int rt_genid_init(struct net *net)
 {
 	atomic_set(&net->ipv4.rt_genid, 0);
 	atomic_set(&net->fnhe_genid, 0);
-	get_random_bytes(&net->ipv4.dev_addr_genid,
-			 sizeof(net->ipv4.dev_addr_genid));
+	atomic_set(&net->ipv4.dev_addr_genid, get_random_int());
 	return 0;
 }
 
-- 
2.13.0

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH v5 00/13] Unseeded In-Kernel Randomness Fixes "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 13/13] random: warn when kernel uses unseeded randomness "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 06/13] iscsi: ensure RNG is seeded before use "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 05/13] crypto/rng: ensure that the RNG is ready before using "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 11/13] net/route: use get_random_int for random counter "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 10/13] net/neighbor: use get_random_u32 for 32-bit hash random "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 08/13] cifs: use get_random_u32 for 32-bit lock random "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 12/13] bluetooth/smp: ensure RNG is properly seeded before ECDH use "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 02/13] random: add synchronous API for the urandom pool "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 01/13] random: invalidate batched entropy after crng init "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
    Re: [PATCH v5 01/13] random: invalidate batched entropy after crng  init Sebastian Andrzej Siewior <sebastian@breakpoint.cc> - 2017-06-14 21:40 +0200
      Re: [PATCH v5 01/13] random: invalidate batched entropy after crng init "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-15 00:40 +0200
        Re: [PATCH v5 01/13] random: invalidate batched entropy after crng  init Sebastian Andrzej Siewior <sebastian@breakpoint.cc> - 2017-06-16 10:40 +0200
          Re: [PATCH v5 01/13] random: invalidate batched entropy after crng init "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-16 14:20 +0200
            Re: [PATCH v5 01/13] random: invalidate batched entropy after crng  init Sebastian Andrzej Siewior <sebastian@breakpoint.cc> - 2017-06-16 16:40 +0200
      [PATCH] random: silence compiler warnings and fix race "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-15 00:50 +0200
        Re: [PATCH] random: silence compiler warnings and fix race Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2017-06-16 16:40 +0200
          Re: [PATCH] random: silence compiler warnings and fix race "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-17 02:40 +0200
            Re: [PATCH] random: silence compiler warnings and fix race Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2017-06-19 09:50 +0200
              Re: [PATCH] random: silence compiler warnings and fix race "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-19 23:00 +0200
        Re: [PATCH] random: silence compiler warnings and fix race "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-19 23:00 +0200
  [PATCH v5 03/13] random: add get_random_{bytes,u32,u64,int,long,once}_wait family "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200
  [PATCH v5 04/13] security/keys: ensure RNG is seeded before use "Jason A. Donenfeld" <Jason@zx2c4.com> - 2017-06-08 01:30 +0200

csiph-web