Linux cryptographic layer development
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From: "Jason A. Donenfeld" <Jason@zx2c4.com>
To: Theodore Ts'o <tytso@mit.edu>,
	Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	kernel-hardening@lists.openwall.com,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Eric Biggers <ebiggers3@gmail.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	David Miller <davem@davemloft.net>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>,
	Thomas Graf <tgraf@suug.ch>,
	Herbert Xu <herbert@gondor.apana.org.au>
Subject: [PATCH v5 09/13] rhashtable: use get_random_u32 for hash_rnd
Date: Thu,  8 Jun 2017 01:26:03 +0200	[thread overview]
Message-ID: <20170607232607.26870-10-Jason@zx2c4.com> (raw)
In-Reply-To: <20170607232607.26870-1-Jason@zx2c4.com>

This is much faster and just as secure. It also has the added benefit of
probably returning better randomness at early-boot on systems with
architectural RNGs.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
---
 lib/rhashtable.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index d9e7274a04cd..a1eb7c947f46 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -235,7 +235,7 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht,
 
 	INIT_LIST_HEAD(&tbl->walkers);
 
-	get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));
+	tbl->hash_rnd = get_random_u32();
 
 	for (i = 0; i < nbuckets; i++)
 		INIT_RHT_NULLS_HEAD(tbl->buckets[i], ht, i);
-- 
2.13.0

  parent reply	other threads:[~2017-06-07 23:26 UTC|newest]

Thread overview: 46+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-07 23:25 [PATCH v5 00/13] Unseeded In-Kernel Randomness Fixes Jason A. Donenfeld
2017-06-07 23:25 ` [PATCH v5 01/13] random: invalidate batched entropy after crng init Jason A. Donenfeld
2017-06-14 19:28   ` Sebastian Andrzej Siewior
2017-06-14 22:33     ` Jason A. Donenfeld
2017-06-16  8:31       ` Sebastian Andrzej Siewior
2017-06-16 12:12         ` Jason A. Donenfeld
2017-06-16 14:36           ` Sebastian Andrzej Siewior
2017-06-14 22:45     ` [PATCH] random: silence compiler warnings and fix race Jason A. Donenfeld
2017-06-16 14:35       ` Sebastian Andrzej Siewior
2017-06-17  0:39         ` Jason A. Donenfeld
2017-06-19  7:45           ` Sebastian Andrzej Siewior
2017-06-19 20:55             ` Jason A. Donenfeld
2017-06-20  6:44               ` Sebastian Andrzej Siewior
2017-06-19 20:57       ` Jason A. Donenfeld
2017-06-20  6:03         ` Theodore Ts'o
2017-06-20  6:27           ` [kernel-hardening] " Joel Stanley
2017-06-20  6:59           ` Michael Ellerman
2017-06-20  8:14           ` Jason A. Donenfeld
2017-06-20  8:33             ` Jeffrey Walton
2017-06-20  8:53               ` Jason A. Donenfeld
2017-06-20  9:36                 ` Theodore Ts'o
2017-06-20  9:49                   ` Jeffrey Walton
2017-06-20 17:50                     ` [kernel-hardening] " Sandy Harris
2017-06-20 18:14                       ` Kees Cook
2017-06-20 20:09                         ` Jason A. Donenfeld
2017-06-20  9:49                   ` Jason A. Donenfeld
2017-06-20 23:38                     ` Theodore Ts'o
2017-06-20 23:54                       ` Jason A. Donenfeld
2017-06-21  0:03                         ` [PATCH] random: warn when kernel uses unseeded randomness Jason A. Donenfeld
2017-06-21  0:12                           ` Kees Cook
2017-06-21  6:06                           ` Michael Ellerman
2017-06-21 20:38                             ` [kernel-hardening] " Theodore Ts'o
2017-06-22  0:04                               ` Jason A. Donenfeld
2017-06-21 23:50                       ` [PATCH] random: silence compiler warnings and fix race Jeffrey Walton
2017-06-07 23:25 ` [PATCH v5 02/13] random: add synchronous API for the urandom pool Jason A. Donenfeld
2017-06-07 23:25 ` [PATCH v5 03/13] random: add get_random_{bytes,u32,u64,int,long,once}_wait family Jason A. Donenfeld
2017-06-07 23:25 ` [PATCH v5 04/13] security/keys: ensure RNG is seeded before use Jason A. Donenfeld
2017-06-07 23:25 ` [PATCH v5 05/13] crypto/rng: ensure that the RNG is ready before using Jason A. Donenfeld
2017-06-07 23:26 ` [PATCH v5 06/13] iscsi: ensure RNG is seeded before use Jason A. Donenfeld
2017-06-07 23:26 ` [PATCH v5 07/13] ceph: ensure RNG is seeded before using Jason A. Donenfeld
2017-06-07 23:26 ` [PATCH v5 08/13] cifs: use get_random_u32 for 32-bit lock random Jason A. Donenfeld
2017-06-07 23:26 ` Jason A. Donenfeld [this message]
2017-06-07 23:26 ` [PATCH v5 10/13] net/neighbor: use get_random_u32 for 32-bit hash random Jason A. Donenfeld
2017-06-07 23:26 ` [PATCH v5 11/13] net/route: use get_random_int for random counter Jason A. Donenfeld
2017-06-07 23:26 ` [PATCH v5 12/13] bluetooth/smp: ensure RNG is properly seeded before ECDH use Jason A. Donenfeld
2017-06-07 23:26 ` [PATCH v5 13/13] random: warn when kernel uses unseeded randomness Jason A. Donenfeld

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