From patchwork Wed Jun 7 23:26:03 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 9773287 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BC20460234 for ; Wed, 7 Jun 2017 23:27:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B190F283AD for ; Wed, 7 Jun 2017 23:27:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A66752848D; Wed, 7 Jun 2017 23:27:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id BCF2E283AD for ; Wed, 7 Jun 2017 23:27:40 +0000 (UTC) Received: (qmail 30570 invoked by uid 550); 7 Jun 2017 23:26:58 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 26349 invoked from network); 7 Jun 2017 23:26:34 -0000 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=zx2c4.com; h=from:to:cc :subject:date:message-id:in-reply-to:references; s=mail; bh=+uHz Y+Igq9iWBc3OsU2692oV8m8=; b=iZLRdfWb8SlOa6qWoqw7KRE/2K8ijY+VuRID 1FVahPoTMblDl13ool3uDVVZPpbiuuraqHxVzJufX27/mYahAvOF7ifT8ctk2Cy1 txX3LcuYmsNZCoYCHvZNkY0/dPpk+LRXzpXR+OFoBFwQHgeJIoDPeZxwz4CyfiK1 +yktTG8A6XZIqs0bHJ7Z8U+uT0j8+TdlifKsW7MDeKoyCMfy2kuHHRHZxkaVBf6y M5kksiuTFa1BdbPNzkeSwaSn3kSJRn4vtbfhyoMHzQ9jyslH7BnohbGB5N+plcA5 02kIIQAGz1iOgv/dQ9chy3UG7DQGPAF3k0M1bf4SX6jl8Qgr7A== From: "Jason A. Donenfeld" To: Theodore Ts'o , Linux Crypto Mailing List , LKML , kernel-hardening@lists.openwall.com, Greg Kroah-Hartman , Eric Biggers , Linus Torvalds , David Miller Cc: "Jason A. Donenfeld" , Thomas Graf , Herbert Xu Date: Thu, 8 Jun 2017 01:26:03 +0200 Message-Id: <20170607232607.26870-10-Jason@zx2c4.com> In-Reply-To: <20170607232607.26870-1-Jason@zx2c4.com> References: <20170607232607.26870-1-Jason@zx2c4.com> Subject: [kernel-hardening] [PATCH v5 09/13] rhashtable: use get_random_u32 for hash_rnd X-Virus-Scanned: ClamAV using ClamSMTP 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 Cc: Thomas Graf Cc: Herbert Xu --- 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);