From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 568DCC43334 for ; Thu, 23 Jun 2022 18:10:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236382AbiFWSK2 (ORCPT ); Thu, 23 Jun 2022 14:10:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48570 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235871AbiFWSGJ (ORCPT ); Thu, 23 Jun 2022 14:06:09 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A8301B2; Thu, 23 Jun 2022 10:18:22 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7555561DE5; Thu, 23 Jun 2022 17:18:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D98BC341C4; Thu, 23 Jun 2022 17:18:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1656004701; bh=nwXc3XpthjYp9ixcMlB2623mIkpfvu/MjJP9HCed4NU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0n8nFJHnznllogMOTYXYJpwum/hH9Hlu8mwYXFtKhuQ9/6Ex4AKQ/YPHWk6Oa0es5 XkSHm8rYAxkCKaXrH1RkZoYveN7ahpJ6bjlZBPvY9PugXpZrsF2LIJtsyYfIxxp/tD V8bGtUYuZRf0sLholzvozIG1gmlSkThZ6PPo1oZA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Theodore Tso , Dominik Brodowski , "Jason A. Donenfeld" Subject: [PATCH 4.19 120/234] random: make consistent usage of crng_ready() Date: Thu, 23 Jun 2022 18:43:07 +0200 Message-Id: <20220623164346.453677394@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220623164343.042598055@linuxfoundation.org> References: <20220623164343.042598055@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Jason A. Donenfeld" commit a96cfe2d427064325ecbf56df8816c6b871ec285 upstream. Rather than sometimes checking `crng_init < 2`, we should always use the crng_ready() macro, so that should we change anything later, it's consistent. Additionally, that macro already has a likely() around it, which means we don't need to open code our own likely() and unlikely() annotations. Cc: Theodore Ts'o Reviewed-by: Dominik Brodowski Signed-off-by: Jason A. Donenfeld Signed-off-by: Greg Kroah-Hartman --- drivers/char/random.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -125,18 +125,13 @@ static void try_to_generate_entropy(void */ int wait_for_random_bytes(void) { - if (likely(crng_ready())) - return 0; - - do { + while (!crng_ready()) { int ret; ret = wait_event_interruptible_timeout(crng_init_wait, crng_ready(), HZ); if (ret) return ret > 0 ? 0 : ret; - try_to_generate_entropy(); - } while (!crng_ready()); - + } return 0; } EXPORT_SYMBOL(wait_for_random_bytes); @@ -291,7 +286,7 @@ static void crng_reseed(void) ++next_gen; WRITE_ONCE(base_crng.generation, next_gen); WRITE_ONCE(base_crng.birth, jiffies); - if (crng_init < 2) { + if (!crng_ready()) { crng_init = 2; finalize_init = true; } @@ -359,7 +354,7 @@ static void crng_make_state(u32 chacha_s * ready, we do fast key erasure with the base_crng directly, because * this is what crng_pre_init_inject() mutates during early init. */ - if (unlikely(!crng_ready())) { + if (!crng_ready()) { bool ready; spin_lock_irqsave(&base_crng.lock, flags); @@ -799,7 +794,7 @@ static void credit_entropy_bits(size_t n entropy_count = min_t(unsigned int, POOL_BITS, orig + add); } while (cmpxchg(&input_pool.entropy_count, orig, entropy_count) != orig); - if (crng_init < 2 && entropy_count >= POOL_MIN_BITS) + if (!crng_ready() && entropy_count >= POOL_MIN_BITS) crng_reseed(); } @@ -956,7 +951,7 @@ int __init rand_initialize(void) extract_entropy(base_crng.key, sizeof(base_crng.key)); ++base_crng.generation; - if (arch_init && trust_cpu && crng_init < 2) { + if (arch_init && trust_cpu && !crng_ready()) { crng_init = 2; pr_notice("crng init done (trusting CPU's manufacturer)\n"); } @@ -1545,7 +1540,7 @@ static long random_ioctl(struct file *f, case RNDRESEEDCRNG: if (!capable(CAP_SYS_ADMIN)) return -EPERM; - if (crng_init < 2) + if (!crng_ready()) return -ENODATA; crng_reseed(); return 0;