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 D3FFDC433F5 for ; Mon, 3 Jan 2022 14:33:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234026AbiACOd4 (ORCPT ); Mon, 3 Jan 2022 09:33:56 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:33000 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234023AbiACObz (ORCPT ); Mon, 3 Jan 2022 09:31:55 -0500 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 15F1B6111D; Mon, 3 Jan 2022 14:31:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EBCF6C36AEB; Mon, 3 Jan 2022 14:31:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1641220314; bh=BZ20Galzn1I8vy3gFLN6Zn7/ni5xt6lwWKK/pr0QZBo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bveJpX1gPnawZ0GBLsB6Nygvu2ViMTlsC+ohelxFaLzN3oP+UPkzdyMEFWzlh+zmU D0Il6k/3lpUpg+jcS5f8nte6cSXPfr5ituZLoj78bTzl+fpuGfkFghmj176YKA9V+n viP7Tx2bzZtYiXtJYmWBn/e0yBf9tsUO2bnkRB3U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Vyukov , Tetsuo Handa , Sasha Levin Subject: [PATCH 5.15 03/73] tomoyo: Check exceeded quota early in tomoyo_domain_quota_is_ok(). Date: Mon, 3 Jan 2022 15:23:24 +0100 Message-Id: <20220103142057.026140766@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220103142056.911344037@linuxfoundation.org> References: <20220103142056.911344037@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: Dmitry Vyukov [ Upstream commit 04e57a2d952bbd34bc45744e72be3eecdc344294 ] If tomoyo is used in a testing/fuzzing environment in learning mode, for lots of domains the quota will be exceeded and stay exceeded for prolonged periods of time. In such cases it's pointless (and slow) to walk the whole acl list again and again just to rediscover that the quota is exceeded. We already have the TOMOYO_DIF_QUOTA_WARNED flag that notes the overflow condition. Check it early to avoid the slowdown. [penguin-kernel] This patch causes a user visible change that the learning mode will not be automatically resumed after the quota is increased. To resume the learning mode, administrator will need to explicitly clear TOMOYO_DIF_QUOTA_WARNED flag after increasing the quota. But I think that this change is generally preferable, for administrator likely wants to optimize the acl list for that domain before increasing the quota, or that domain likely hits the quota again. Therefore, don't try to care to clear TOMOYO_DIF_QUOTA_WARNED flag automatically when the quota for that domain changed. Signed-off-by: Dmitry Vyukov Signed-off-by: Tetsuo Handa Signed-off-by: Sasha Levin --- security/tomoyo/util.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/security/tomoyo/util.c b/security/tomoyo/util.c index 1da2e3722b126..af8cd2af3466d 100644 --- a/security/tomoyo/util.c +++ b/security/tomoyo/util.c @@ -1051,6 +1051,8 @@ bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r) return false; if (!domain) return true; + if (READ_ONCE(domain->flags[TOMOYO_DIF_QUOTA_WARNED])) + return false; list_for_each_entry_rcu(ptr, &domain->acl_info_list, list, srcu_read_lock_held(&tomoyo_ss)) { u16 perm; @@ -1096,14 +1098,12 @@ bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r) if (count < tomoyo_profile(domain->ns, domain->profile)-> pref[TOMOYO_PREF_MAX_LEARNING_ENTRY]) return true; - if (!domain->flags[TOMOYO_DIF_QUOTA_WARNED]) { - domain->flags[TOMOYO_DIF_QUOTA_WARNED] = true; - /* r->granted = false; */ - tomoyo_write_log(r, "%s", tomoyo_dif[TOMOYO_DIF_QUOTA_WARNED]); + WRITE_ONCE(domain->flags[TOMOYO_DIF_QUOTA_WARNED], true); + /* r->granted = false; */ + tomoyo_write_log(r, "%s", tomoyo_dif[TOMOYO_DIF_QUOTA_WARNED]); #ifndef CONFIG_SECURITY_TOMOYO_INSECURE_BUILTIN_SETTING - pr_warn("WARNING: Domain '%s' has too many ACLs to hold. Stopped learning mode.\n", - domain->domainname->name); + pr_warn("WARNING: Domain '%s' has too many ACLs to hold. Stopped learning mode.\n", + domain->domainname->name); #endif - } return false; } -- 2.34.1