From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932525AbcE3Flf (ORCPT ); Mon, 30 May 2016 01:41:35 -0400 Received: from imap.thunk.org ([74.207.234.97]:45512 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161049AbcE3FkN (ORCPT ); Mon, 30 May 2016 01:40:13 -0400 From: "Theodore Ts'o" To: Linux Kernel Developers List Cc: smueller@chronox.de, herbert@gondor.apana.org.au, andi@firstfloor.org, sandyinchina@gmail.com, cryptography@lakedaemon.net, jsd@av8n.com, hpa@zytor.com, linux-crypto@vger.kernel.org, Eric Biggers , "Theodore Ts'o" Subject: [PATCH 5/5] random: properly align get_random_int_hash Date: Mon, 30 May 2016 01:39:25 -0400 Message-Id: <1464586765-14436-6-git-send-email-tytso@mit.edu> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1464586765-14436-1-git-send-email-tytso@mit.edu> References: <1464586765-14436-1-git-send-email-tytso@mit.edu> X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Biggers get_random_long() reads from the get_random_int_hash array using an unsigned long pointer. For this code to be guaranteed correct on all architectures, the array must be aligned to an unsigned long boundary. Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o --- drivers/char/random.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index 860862f..90fb569 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -2033,13 +2033,15 @@ int random_int_secret_init(void) return 0; } +static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash) + __aligned(sizeof(unsigned long)); + /* * Get a random word for internal kernel use only. Similar to urandom but * with the goal of minimal entropy pool depletion. As a result, the random * value is not cryptographically secure but for several uses the cost of * depleting entropy is too high */ -static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash); unsigned int get_random_int(void) { __u32 *hash; -- 2.5.0