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 59870ECAAD3 for ; Fri, 9 Sep 2022 14:53:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231960AbiIIOx4 (ORCPT ); Fri, 9 Sep 2022 10:53:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38348 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231703AbiIIOxy (ORCPT ); Fri, 9 Sep 2022 10:53:54 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AEDBD1332AE; Fri, 9 Sep 2022 07:53:52 -0700 (PDT) Received: from fraeml701-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4MPJrB6nRSz67lnC; Fri, 9 Sep 2022 22:52:42 +0800 (CST) Received: from lhrpeml500004.china.huawei.com (7.191.163.9) by fraeml701-chm.china.huawei.com (10.206.15.50) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2375.31; Fri, 9 Sep 2022 16:53:49 +0200 Received: from [10.122.132.241] (10.122.132.241) by lhrpeml500004.china.huawei.com (7.191.163.9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Fri, 9 Sep 2022 15:53:49 +0100 Message-ID: <72db3ee6-06ee-0af8-06c6-ac16200bb83f@huawei.com> Date: Fri, 9 Sep 2022 17:53:48 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.4.1 Subject: Re: [PATCH v7 03/18] landlock: refactor merge/inherit_ruleset functions Content-Language: ru To: =?UTF-8?Q?Micka=c3=abl_Sala=c3=bcn?= CC: , , , , , References: <20220829170401.834298-1-konstantin.meskhidze@huawei.com> <20220829170401.834298-4-konstantin.meskhidze@huawei.com> <6839cc81-fa34-cda9-91d3-89f63750795c@digikod.net> From: "Konstantin Meskhidze (A)" In-Reply-To: <6839cc81-fa34-cda9-91d3-89f63750795c@digikod.net> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.122.132.241] X-ClientProxiedBy: lhrpeml500005.china.huawei.com (7.191.163.240) To lhrpeml500004.china.huawei.com (7.191.163.9) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org 9/6/2022 11:07 AM, Mickaël Salaün пишет: > > On 29/08/2022 19:03, Konstantin Meskhidze wrote: >> Refactors merge_ruleset() and inherit_ruleset() functions to support >> new rule types. This patch adds merge_tree() and inherit_tree() >> helpers. Each has key_type argument to choose a particular rb_tree >> structure in a ruleset. >> >> Signed-off-by: Konstantin Meskhidze >> --- >> >> Changes since v6: >> * Refactors merge_ruleset() and inherit_ruleset() functions to support >> new rule types. >> * Renames tree_merge() to merge_tree() (and reorder arguments), and >> tree_copy() to inherit_tree(). >> >> Changes since v5: >> * Refactors some logic errors. >> * Formats code with clang-format-14. >> >> Changes since v4: >> * None >> >> --- >> security/landlock/ruleset.c | 108 +++++++++++++++++++++++------------- >> 1 file changed, 69 insertions(+), 39 deletions(-) >> >> diff --git a/security/landlock/ruleset.c b/security/landlock/ruleset.c >> index 41de17d1869e..3a5ef356aaa3 100644 >> --- a/security/landlock/ruleset.c >> +++ b/security/landlock/ruleset.c >> @@ -302,36 +302,18 @@ static void put_hierarchy(struct landlock_hierarchy *hierarchy) >> } >> } >> >> -static int merge_ruleset(struct landlock_ruleset *const dst, >> - struct landlock_ruleset *const src) >> +static int merge_tree(struct landlock_ruleset *const dst, >> + struct landlock_ruleset *const src, >> + const enum landlock_key_type key_type) >> { >> struct landlock_rule *walker_rule, *next_rule; >> struct rb_root *src_root; >> int err = 0; >> >> - might_sleep(); >> - /* Should already be checked by landlock_merge_ruleset() */ >> - if (WARN_ON_ONCE(!src)) >> - return 0; >> - /* Only merge into a domain. */ >> - if (WARN_ON_ONCE(!dst || !dst->hierarchy)) >> - return -EINVAL; >> - >> - src_root = get_root(src, LANDLOCK_KEY_INODE); > > This hunk is a bit misleading, but please add a might_sleep() call here > because of the insert_rule() call, and some lock asserts: > > might_sleep(); > lockdep_assert_held(&dst->lock); > lockdep_assert_held(&src->lock); it was moved into merge_ruleset() function, please check below. > > >> + src_root = get_root(src, key_type); >> if (IS_ERR(src_root)) >> return PTR_ERR(src_root); >> >> - /* Locks @dst first because we are its only owner. */ >> - mutex_lock(&dst->lock); >> - mutex_lock_nested(&src->lock, SINGLE_DEPTH_NESTING); >> - >> - /* Stacks the new layer. */ >> - if (WARN_ON_ONCE(src->num_layers != 1 || dst->num_layers < 1)) { >> - err = -EINVAL; >> - goto out_unlock; >> - } >> - dst->access_masks[dst->num_layers - 1] = src->access_masks[0]; >> - >> /* Merges the @src tree. */ >> rbtree_postorder_for_each_entry_safe(walker_rule, next_rule, src_root, >> node) { >> @@ -340,7 +322,7 @@ static int merge_ruleset(struct landlock_ruleset *const dst, >> } }; >> const struct landlock_id id = { >> .key = walker_rule->key, >> - .type = LANDLOCK_KEY_INODE, >> + .type = key_type, >> }; >> >> if (WARN_ON_ONCE(walker_rule->num_layers != 1)) >> @@ -351,8 +333,39 @@ static int merge_ruleset(struct landlock_ruleset *const dst, >> >> err = insert_rule(dst, id, &layers, ARRAY_SIZE(layers)); >> if (err) >> - goto out_unlock; >> + return err; >> + } >> + return err; >> +} >> + >> +static int merge_ruleset(struct landlock_ruleset *const dst, >> + struct landlock_ruleset *const src) >> +{ >> + int err = 0; >> + >> + might_sleep(); >> + /* Should already be checked by landlock_merge_ruleset() */ >> + if (WARN_ON_ONCE(!src)) >> + return 0; >> + /* Only merge into a domain. */ >> + if (WARN_ON_ONCE(!dst || !dst->hierarchy)) >> + return -EINVAL; >> + >> + /* Locks @dst first because we are its only owner. */ >> + mutex_lock(&dst->lock); >> + mutex_lock_nested(&src->lock, SINGLE_DEPTH_NESTING); >> + >> + /* Stacks the new layer. */ >> + if (WARN_ON_ONCE(src->num_layers != 1 || dst->num_layers < 1)) { >> + err = -EINVAL; >> + goto out_unlock; >> } >> + dst->access_masks[dst->num_layers - 1] = src->access_masks[0]; >> + >> + /* Merges the @src inode tree. */ >> + err = merge_tree(dst, src, LANDLOCK_KEY_INODE); >> + if (err) >> + goto out_unlock; >> >> out_unlock: >> mutex_unlock(&src->lock); >> @@ -360,43 +373,60 @@ static int merge_ruleset(struct landlock_ruleset *const dst, >> return err; >> } >> >> -static int inherit_ruleset(struct landlock_ruleset *const parent, >> - struct landlock_ruleset *const child) >> +static int inherit_tree(struct landlock_ruleset *const parent, >> + struct landlock_ruleset *const child, >> + const enum landlock_key_type key_type) >> { >> struct landlock_rule *walker_rule, *next_rule; >> struct rb_root *parent_root; >> int err = 0; >> >> - might_sleep(); >> - if (!parent) >> - return 0; >> - >> - parent_root = get_root(parent, LANDLOCK_KEY_INODE); > > This hunk is a bit misleading, but please add a might_sleep() call here > because of the insert_rule() call, and some lock asserts: > > might_sleep(); > lockdep_assert_held(&parent->lock); > lockdep_assert_held(&child->lock); > it was moved into inherit_ruleset() function, please check below. > >> + parent_root = get_root(parent, key_type); >> if (IS_ERR(parent_root)) >> return PTR_ERR(parent_root); >> >> - /* Locks @child first because we are its only owner. */ >> - mutex_lock(&child->lock); >> - mutex_lock_nested(&parent->lock, SINGLE_DEPTH_NESTING); >> - >> - /* Copies the @parent tree. */ >> + /* Copies the @parent inode or network tree. */ >> rbtree_postorder_for_each_entry_safe(walker_rule, next_rule, >> parent_root, node) { >> const struct landlock_id id = { >> .key = walker_rule->key, >> - .type = LANDLOCK_KEY_INODE, >> + .type = key_type, >> }; >> + >> err = insert_rule(child, id, &walker_rule->layers, >> walker_rule->num_layers); >> if (err) >> - goto out_unlock; >> + return err; >> } >> + return err; >> +} >> + >> +static int inherit_ruleset(struct landlock_ruleset *const parent, >> + struct landlock_ruleset *const child) >> +{ >> + int err = 0; >> + >> + might_sleep(); >> + if (!parent) >> + return 0; >> + >> + /* Locks @child first because we are its only owner. */ >> + mutex_lock(&child->lock); >> + mutex_lock_nested(&parent->lock, SINGLE_DEPTH_NESTING); >> + >> + /* Copies the @parent inode tree. */ >> + err = inherit_tree(parent, child, LANDLOCK_KEY_INODE); >> + if (err) >> + goto out_unlock; >> >> if (WARN_ON_ONCE(child->num_layers <= parent->num_layers)) { >> err = -EINVAL; >> goto out_unlock; >> } >> - /* Copies the parent layer stack and leaves a space for the new layer. */ >> + /* >> + * Copies the parent layer stack and leaves a space >> + * for the new layer. >> + */ >> memcpy(child->access_masks, parent->access_masks, >> flex_array_size(parent, access_masks, parent->num_layers)); >> >> -- >> 2.25.1 >> > .