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 A82C2C77B72 for ; Thu, 20 Apr 2023 11:46:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234375AbjDTLqo (ORCPT ); Thu, 20 Apr 2023 07:46:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46016 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233808AbjDTLqn (ORCPT ); Thu, 20 Apr 2023 07:46:43 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA75C1FF0; Thu, 20 Apr 2023 04:46:41 -0700 (PDT) Received: from lhrpeml500004.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Q2G5M1JTQz6J773; Thu, 20 Apr 2023 19:43:51 +0800 (CST) Received: from [10.123.123.126] (10.123.123.126) 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 15.1.2507.23; Thu, 20 Apr 2023 12:46:38 +0100 Message-ID: <13792f4e-3df7-9cc0-734a-285f95dbe7ca@huawei.com> Date: Thu, 20 Apr 2023 14:46:38 +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 v10 05/13] landlock: Refactor merge/inherit_ruleset functions Content-Language: ru To: =?UTF-8?Q?Micka=c3=abl_Sala=c3=bcn?= CC: , , , , , , References: <20230323085226.1432550-1-konstantin.meskhidze@huawei.com> <20230323085226.1432550-6-konstantin.meskhidze@huawei.com> <8b2f2e0f-0a95-ef87-7eb2-286e75a62e2c@digikod.net> From: "Konstantin Meskhidze (A)" In-Reply-To: <8b2f2e0f-0a95-ef87-7eb2-286e75a62e2c@digikod.net> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.123.123.126] 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: 4/16/2023 7:09 PM, Mickaël Salaün пишет: > > On 23/03/2023 09:52, Konstantin Meskhidze wrote: >> Refactor merge_ruleset() and inherit_ruleset() functions to support >> new rule types. This patch adds merge_tree() and inherit_tree() >> helpers. They use a specific ruleset's red-black tree according to >> a key type argument. >> >> Signed-off-by: Konstantin Meskhidze >> --- >> >> Changes since v9: >> * None >> >> Changes since v8: >> * Refactors commit message. >> * Minor fixes. >> >> Changes since v7: >> * Adds missed lockdep_assert_held it inherit_tree() and merge_tree(). >> * Fixes comment. >> >> 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 | 110 ++++++++++++++++++++++++------------ >> 1 file changed, 73 insertions(+), 37 deletions(-) >> >> diff --git a/security/landlock/ruleset.c b/security/landlock/ruleset.c >> index d3859d5e7306..2579c9bbedbc 100644 >> --- a/security/landlock/ruleset.c >> +++ b/security/landlock/ruleset.c >> @@ -302,36 +302,22 @@ 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; >> + lockdep_assert_held(&dst->lock); >> + lockdep_assert_held(&src->lock); >> >> - src_root = get_root(src, LANDLOCK_KEY_INODE); >> + 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) { >> @@ -340,23 +326,52 @@ 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)) { >> err = -EINVAL; >> - goto out_unlock; > > This should be replaced with `return -EINVAL;` and the `{` `}` after the > if condition are not needed anymore. > Ok. Will be changed. > >> } >> if (WARN_ON_ONCE(walker_rule->layers[0].level != 0)) { >> err = -EINVAL; >> - goto out_unlock; > > ditto Got it. > >> } >> layers[0].access = walker_rule->layers[0].access; >> >> 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); >> @@ -364,43 +379,64 @@ 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; >> + lockdep_assert_held(&parent->lock); >> + lockdep_assert_held(&child->lock); >> >> - parent_root = get_root(parent, LANDLOCK_KEY_INODE); >> + 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 >> > .