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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62E47C4332F for ; Sun, 11 Dec 2022 22:16:31 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EFB128E0006; Sun, 11 Dec 2022 17:16:30 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id EAAEB8E0002; Sun, 11 Dec 2022 17:16:30 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D4AA78E0006; Sun, 11 Dec 2022 17:16:30 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id C29DD8E0002 for ; Sun, 11 Dec 2022 17:16:30 -0500 (EST) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 75ED91C5B03 for ; Sun, 11 Dec 2022 22:16:30 +0000 (UTC) X-FDA: 80231435340.06.D3BD5FC Received: from mail-wr1-f45.google.com (mail-wr1-f45.google.com [209.85.221.45]) by imf23.hostedemail.com (Postfix) with ESMTP id C8B7A14000E for ; Sun, 11 Dec 2022 22:16:28 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=mail.huji.ac.il header.s=mailhuji header.b="UbLp/WJd"; spf=pass (imf23.hostedemail.com: domain of david.keisarschm@mail.huji.ac.il designates 209.85.221.45 as permitted sender) smtp.mailfrom=david.keisarschm@mail.huji.ac.il; dmarc=pass (policy=none) header.from=huji.ac.il ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1670796988; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=haTxffWmHSbAPwv39fal7v0AA4S/hzfP5R1mLvgRpek=; b=lXFdijlEXfalitMR7FIk3UE5y2quLBqcmQml/ICs9mLcP8QV7AoC78jHwvgTIu96t2fpfs E689B/lYEeTUqPqlETXefJMR0ShjyUBUdGtub65NjdAe/cSqNcnFPE8/mWEm6CpdvBLKR2 WLCf0JXPjS201KqT89yaV1ufK8xSQcc= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=mail.huji.ac.il header.s=mailhuji header.b="UbLp/WJd"; spf=pass (imf23.hostedemail.com: domain of david.keisarschm@mail.huji.ac.il designates 209.85.221.45 as permitted sender) smtp.mailfrom=david.keisarschm@mail.huji.ac.il; dmarc=pass (policy=none) header.from=huji.ac.il ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1670796988; a=rsa-sha256; cv=none; b=sylYeid6Tne1m4Cz9UXyrK/JyBz9OWa1vaVcf99y6xjkmB+5uzVL5NjlTrN1Ypkml5a5zP F3i3lTObgoxQHW2qu5HQUFJYbY7TtSyzIJ0gPvI5OdvtgUdRz33AVgoNmKvqkzms83rti/ LhKK9iMqQVpjKnH2Z37uD8tr8CfrhyM= Received: by mail-wr1-f45.google.com with SMTP id y16so10321444wrm.2 for ; Sun, 11 Dec 2022 14:16:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mail.huji.ac.il; s=mailhuji; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=haTxffWmHSbAPwv39fal7v0AA4S/hzfP5R1mLvgRpek=; b=UbLp/WJdGEjbrNFkSsIuV78VgoO68KxhGH2WYTQpJtOfXrKCllm7Y+e+mOcVYVBjmd 54ZjcvsZUdzXyeVth+DloJ5pZNO1lLMOm4QQA5AqbesJaSqGG0SKj2+MBqhmW8fczXDm rFe1P4tp6xRSDbJjsqwUHsIkj5X77hGVZleuI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=haTxffWmHSbAPwv39fal7v0AA4S/hzfP5R1mLvgRpek=; b=ip69Ja3mWAOBB9QmUsCrJsLrwSLe+Us/vbnqlKS2fLBQJ1BP0n7zBFTDPTl6I6pFLb jXWvvZDLuUc3nu3IKskV75kelYjVRRtv6av9kZWE66KUfOMUbHDDOu0176dPL1cLkF7m P0nlIzQY5Gg7PuuxzlEfFn432Dv5YZDveAmaK2ZUH1NsitGGoVKNZy7Z758+YwGjPqTa 2fQtwyjemxVWoMzwHi9wfuN37AE87YfP87bs78h8P2rJw14+yWBXUdkdcJvZUiBheG69 QlacGWBHC6s+oCLid0/VgNww4yixY2/hFIy9TCvim+Ep7l8rw0758gKbcSYNREiqr8yi 6KMg== X-Gm-Message-State: ANoB5pmlgxWc3V/4MESBjM+BnrVGV9Qc6jfAwO9eF3n2nsGAUDOqrtn1 IeaJBMLImZfTSqNBMfbNbZpo4w== X-Google-Smtp-Source: AA0mqf4+pbXX8gZcvwBJDDX/GsbtFqpKUq1E1bX85Vp1pP715Zv9EOXv/m3uGnNCBqE5llnuBJD80w== X-Received: by 2002:a5d:4090:0:b0:24d:5829:4e59 with SMTP id o16-20020a5d4090000000b0024d58294e59mr4060976wrp.58.1670796987434; Sun, 11 Dec 2022 14:16:27 -0800 (PST) Received: from MacBook-Pro-5.lan ([2a0d:6fc2:218c:1a00:a91c:f8bf:c26f:4f15]) by smtp.gmail.com with ESMTPSA id d7-20020adffd87000000b002422bc69111sm8605805wrr.9.2022.12.11.14.16.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 11 Dec 2022 14:16:27 -0800 (PST) From: david.keisarschm@mail.huji.ac.il To: Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: David , aksecurity@gmail.com, ilay.bahat1@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 4/5] Replace invocation of weak PRNG inside mm/slab_common.c Date: Mon, 12 Dec 2022 00:16:07 +0200 Message-Id: <095bc8aafcc97d6a53d1f946a9528b10a826116d.1670778652.git.david.keisarschm@mail.huji.ac.il> X-Mailer: git-send-email 2.38.0 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Stat-Signature: aqtijwa5tb977eebrb4kjoor6r89u9f1 X-Rspam-User: X-Rspamd-Queue-Id: C8B7A14000E X-Rspamd-Server: rspam06 X-HE-Tag: 1670796988-668903 X-HE-Meta: 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 22q3C1st M0DKdnk4As/y1+8k0PRL0edeekNkd20q+mHMzaCxTk71jbcx7I8IMxR581iua0NshjCVviHnq1rP8EUVWd6v4cGXDoBR7ukDBj0R0izynT0L0m+39VxBdJYJRIRlnCrpjYBL/TMU/eXwFEAaAwVwi0woimsmcm/IPxk9i9HCCSkoh/FueNy3EubwP7lsudvy00ycskFSJEXS6n3jMdpx221MKY7d5Wa6LLNYR+t/4pHXEJ+QRP4RFV4lz+D9bVVi1xYOHbUgSsJAAsA8= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: David We changed the invocation of prandom_u32_state to get_random_u32. We also omitted the initial seeding for the state, since get_random_u32 maintains its own, so there is no need to keep storing the state of prandom_u32_state here. Signed-off-by: David --- mm/slab_common.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/mm/slab_common.c b/mm/slab_common.c index deb764785..6ac68b9a6 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -1130,7 +1130,7 @@ EXPORT_SYMBOL(kmalloc_large_node); #ifdef CONFIG_SLAB_FREELIST_RANDOM /* Randomize a generic freelist */ -static void freelist_randomize(struct rnd_state *state, unsigned int *list, +static void freelist_randomize(unsigned int *list, unsigned int count) { unsigned int rand; @@ -1141,7 +1141,7 @@ static void freelist_randomize(struct rnd_state *state, unsigned int *list, /* Fisher-Yates shuffle */ for (i = count - 1; i > 0; i--) { - rand = predictable_rng_prandom_u32_state(state); + rand = get_random_u32(); rand %= (i + 1); swap(list[i], list[rand]); } @@ -1151,7 +1151,6 @@ static void freelist_randomize(struct rnd_state *state, unsigned int *list, int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, gfp_t gfp) { - struct rnd_state state; if (count < 2 || cachep->random_seq) return 0; @@ -1160,10 +1159,7 @@ int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, if (!cachep->random_seq) return -ENOMEM; - /* Get best entropy at this stage of boot */ - prandom_seed_state(&state, get_random_long()); - - freelist_randomize(&state, cachep->random_seq, count); + freelist_randomize(cachep->random_seq, count); return 0; } -- 2.38.0