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 49FBBECAAD3 for ; Sat, 10 Sep 2022 18:27:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229607AbiIJS1i (ORCPT ); Sat, 10 Sep 2022 14:27:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59912 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229583AbiIJS1h (ORCPT ); Sat, 10 Sep 2022 14:27:37 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A796241D27; Sat, 10 Sep 2022 11:27:34 -0700 (PDT) Received: from fraeml741-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4MQ1Sk3GGjz67p52; Sun, 11 Sep 2022 02:23:18 +0800 (CST) Received: from lhrpeml500004.china.huawei.com (7.191.163.9) by fraeml741-chm.china.huawei.com (10.206.15.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Sat, 10 Sep 2022 20:27:31 +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; Sat, 10 Sep 2022 19:27:30 +0100 Message-ID: <1563a50e-e345-4abb-1c4d-45284102ca6b@huawei.com> Date: Sat, 10 Sep 2022 21:27:29 +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 08/18] landlock: add network rules support Content-Language: ru To: =?UTF-8?Q?Micka=c3=abl_Sala=c3=bcn?= CC: , , , , , References: <20220829170401.834298-1-konstantin.meskhidze@huawei.com> <20220829170401.834298-9-konstantin.meskhidze@huawei.com> <9cf95acb-14a0-0900-c5af-c910de80e289@digikod.net> From: "Konstantin Meskhidze (A)" In-Reply-To: <9cf95acb-14a0-0900-c5af-c910de80e289@digikod.net> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.122.132.241] X-ClientProxiedBy: lhrpeml500004.china.huawei.com (7.191.163.9) 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 11:08 AM, Mickaël Salaün пишет: > > On 29/08/2022 19:03, Konstantin Meskhidze wrote: >> This commit adds network rules support in internal landlock functions >> (presented in ruleset.c) and landlock_create_ruleset syscall. >> >> Signed-off-by: Konstantin Meskhidze >> --- >> >> Changes since v6: >> * Renames landlock_set_net_access_mask() to landlock_add_net_access_mask() >> because it OR values. >> * Makes landlock_add_net_access_mask() more resilient incorrect values. >> * Refactors landlock_get_net_access_mask(). >> * Renames LANDLOCK_MASK_SHIFT_NET to LANDLOCK_SHIFT_ACCESS_NET and use >> LANDLOCK_NUM_ACCESS_FS as value. >> * Updates access_masks_t to u32 to support network access actions. >> * Refactors landlock internal functions to support network actions with >> landlock_key/key_type/id types. >> >> Changes since v5: >> * Gets rid of partial revert from landlock_add_rule >> syscall. >> * Formats code with clang-format-14. >> >> Changes since v4: >> * Refactors landlock_create_ruleset() - splits ruleset and >> masks checks. >> * Refactors landlock_create_ruleset() and landlock mask >> setters/getters to support two rule types. >> * Refactors landlock_add_rule syscall add_rule_path_beneath >> function by factoring out get_ruleset_from_fd() and >> landlock_put_ruleset(). >> >> Changes since v3: >> * Splits commit. >> * Adds network rule support for internal landlock functions. >> * Adds set_mask and get_mask for network. >> * Adds rb_root root_net_port. >> >> --- >> security/landlock/limits.h | 6 +++++- >> security/landlock/ruleset.c | 38 +++++++++++++++++++++++++++++---- >> security/landlock/ruleset.h | 41 ++++++++++++++++++++++++++++++++++-- >> security/landlock/syscalls.c | 8 ++++++- >> 4 files changed, 85 insertions(+), 8 deletions(-) >> >> diff --git a/security/landlock/limits.h b/security/landlock/limits.h >> index bafb3b8dc677..8a1a6463c64e 100644 >> --- a/security/landlock/limits.h >> +++ b/security/landlock/limits.h >> @@ -23,6 +23,10 @@ >> #define LANDLOCK_NUM_ACCESS_FS __const_hweight64(LANDLOCK_MASK_ACCESS_FS) >> #define LANDLOCK_SHIFT_ACCESS_FS 0 >> >> -/* clang-format on */ >> +#define LANDLOCK_LAST_ACCESS_NET LANDLOCK_ACCESS_NET_CONNECT_TCP >> +#define LANDLOCK_MASK_ACCESS_NET ((LANDLOCK_LAST_ACCESS_NET << 1) - 1) >> +#define LANDLOCK_NUM_ACCESS_NET __const_hweight64(LANDLOCK_MASK_ACCESS_NET) >> +#define LANDLOCK_SHIFT_ACCESS_NET LANDLOCK_NUM_ACCESS_FS >> >> +/* clang-format on */ >> #endif /* _SECURITY_LANDLOCK_LIMITS_H */ >> diff --git a/security/landlock/ruleset.c b/security/landlock/ruleset.c >> index 84fcd8eb30d4..442f212039df 100644 >> --- a/security/landlock/ruleset.c >> +++ b/security/landlock/ruleset.c >> @@ -36,6 +36,7 @@ static struct landlock_ruleset *create_ruleset(const u32 num_layers) >> refcount_set(&new_ruleset->usage, 1); >> mutex_init(&new_ruleset->lock); >> new_ruleset->root_inode = RB_ROOT; >> + new_ruleset->root_net_port = RB_ROOT; >> new_ruleset->num_layers = num_layers; >> /* >> * hierarchy = NULL >> @@ -46,16 +47,21 @@ static struct landlock_ruleset *create_ruleset(const u32 num_layers) >> } >> >> struct landlock_ruleset * >> -landlock_create_ruleset(const access_mask_t fs_access_mask) >> +landlock_create_ruleset(const access_mask_t fs_access_mask, >> + const access_mask_t net_access_mask) >> { >> struct landlock_ruleset *new_ruleset; >> >> /* Informs about useless ruleset. */ >> - if (!fs_access_mask) >> + if (!fs_access_mask && !net_access_mask) >> return ERR_PTR(-ENOMSG); >> new_ruleset = create_ruleset(1); >> - if (!IS_ERR(new_ruleset)) >> + if (IS_ERR(new_ruleset)) >> + return new_ruleset; >> + if (fs_access_mask) >> landlock_add_fs_access_mask(new_ruleset, fs_access_mask, 0); >> + if (net_access_mask) >> + landlock_add_net_access_mask(new_ruleset, net_access_mask, 0); >> return new_ruleset; >> } >> >> @@ -73,6 +79,8 @@ static inline bool is_object_pointer(const enum landlock_key_type key_type) >> switch (key_type) { >> case LANDLOCK_KEY_INODE: >> return true; >> + case LANDLOCK_KEY_NET_PORT: >> + return false; >> } >> WARN_ON_ONCE(1); >> return false; >> @@ -126,6 +134,9 @@ static inline struct rb_root *get_root(struct landlock_ruleset *const ruleset, >> case LANDLOCK_KEY_INODE: >> root = &ruleset->root_inode; >> break; >> + case LANDLOCK_KEY_NET_PORT: >> + root = &ruleset->root_net_port; >> + break; >> } >> if (WARN_ON_ONCE(!root)) >> return ERR_PTR(-EINVAL); >> @@ -154,7 +165,9 @@ static void build_check_ruleset(void) >> BUILD_BUG_ON(ruleset.num_rules < LANDLOCK_MAX_NUM_RULES); >> BUILD_BUG_ON(ruleset.num_layers < LANDLOCK_MAX_NUM_LAYERS); >> BUILD_BUG_ON(access_masks < >> - (LANDLOCK_MASK_ACCESS_FS << LANDLOCK_SHIFT_ACCESS_FS)); >> + (LANDLOCK_MASK_ACCESS_FS << LANDLOCK_SHIFT_ACCESS_FS) + >> + (LANDLOCK_MASK_ACCESS_NET >> + << LANDLOCK_SHIFT_ACCESS_NET)); >> } >> >> /** >> @@ -367,6 +380,11 @@ static int merge_ruleset(struct landlock_ruleset *const dst, >> if (err) >> goto out_unlock; >> >> + /* Merges the @src network port tree. */ >> + err = merge_tree(dst, src, LANDLOCK_KEY_NET_PORT); >> + if (err) >> + goto out_unlock; >> + >> out_unlock: >> mutex_unlock(&src->lock); >> mutex_unlock(&dst->lock); >> @@ -419,6 +437,11 @@ static int inherit_ruleset(struct landlock_ruleset *const parent, >> if (err) >> goto out_unlock; >> >> + /* Copies the @parent network port tree. */ >> + err = inherit_tree(parent, child, LANDLOCK_KEY_NET_PORT); >> + if (err) >> + goto out_unlock; >> + >> if (WARN_ON_ONCE(child->num_layers <= parent->num_layers)) { >> err = -EINVAL; >> goto out_unlock; >> @@ -451,6 +474,9 @@ static void free_ruleset(struct landlock_ruleset *const ruleset) >> rbtree_postorder_for_each_entry_safe(freeme, next, &ruleset->root_inode, >> node) >> free_rule(freeme, LANDLOCK_KEY_INODE); >> + rbtree_postorder_for_each_entry_safe(freeme, next, >> + &ruleset->root_net_port, node) >> + free_rule(freeme, LANDLOCK_KEY_NET_PORT); >> put_hierarchy(ruleset->hierarchy); >> kfree(ruleset); >> } >> @@ -640,6 +666,10 @@ access_mask_t init_layer_masks(const struct landlock_ruleset *const domain, >> get_access_mask = landlock_get_fs_access_mask; >> num_access = LANDLOCK_NUM_ACCESS_FS; >> break; >> + case LANDLOCK_KEY_NET_PORT: >> + get_access_mask = landlock_get_net_access_mask; >> + num_access = LANDLOCK_NUM_ACCESS_NET; >> + break; >> default: >> WARN_ON_ONCE(1); >> return 0; >> diff --git a/security/landlock/ruleset.h b/security/landlock/ruleset.h >> index 2083855bf42d..d456ee90b648 100644 >> --- a/security/landlock/ruleset.h >> +++ b/security/landlock/ruleset.h >> @@ -26,7 +26,7 @@ static_assert(BITS_PER_TYPE(access_mask_t) >= LANDLOCK_NUM_ACCESS_FS); >> static_assert(sizeof(unsigned long) >= sizeof(access_mask_t)); >> >> /* Ruleset access masks. */ >> -typedef u16 access_masks_t; >> +typedef u32 access_masks_t; >> /* Makes sure all ruleset access rights can be stored. */ >> static_assert(BITS_PER_TYPE(access_masks_t) >= LANDLOCK_NUM_ACCESS_FS); > > There is some fixes missing from my patch. > > >> >> @@ -66,6 +66,11 @@ enum landlock_key_type { >> * keys. >> */ >> LANDLOCK_KEY_INODE = 1, > > > #if IS_ENABLED(CONFIG_INET) > >> + /** >> + * @LANDLOCK_KEY_NET_PORT: Type of &landlock_ruleset.root_net_port's >> + * node keys. >> + */ >> + LANDLOCK_KEY_NET_PORT = 2, > > #endif /* IS_ENABLED(CONFIG_INET) */ > > And then all use of LANDLOCK_KEY_NET_PORT should be surrounded by the > same check (but not directly in the net.c file). I checked the branch with your patches: tmp-net (7d6cf40a6f81adf607ad3cc17aaa11e256beeea4), but I did not find #if IS_ENABLED(CONFIG_INET) surrounding LANDLOCK_KEY_NET_PORT. > > >> }; >> >> /** >> @@ -133,6 +138,12 @@ struct landlock_ruleset { >> * reaches zero. >> */ >> struct rb_root root_inode; > > #if IS_ENABLED(CONFIG_INET) > >> + /** >> + * @root_net_port: Root of a red-black tree containing object nodes >> + * for network port. Once a ruleset is tied to a process (i.e. as a domain), >> + * this tree is immutable until @usage reaches zero. >> + */ > > There is some fixes missing from my patch. Please explain everything > that you didn't take. Sorry. I did merge your patch manually and did not tell the difference here. Will be fixed > > >> + struct rb_root root_net_port; > > > #endif /* IS_ENABLED(CONFIG_INET) */ > > And then all use of root_net_port should be surrounded by the same check. The same - I did not find #if IS_ENABLED(CONFIG_INET) surrounding root_net_port in tmp-net (7d6cf40a6f81adf607ad3cc17aaa11e256beeea4) > > I think it should be OK to keep all other remaining network references > though (e.g. access_masks and the ). Ok. Thanks. > > >> /** >> * @hierarchy: Enables hierarchy identification even when a parent >> * domain vanishes. This is needed for the ptrace protection. >> @@ -188,7 +199,8 @@ struct landlock_ruleset { >> }; >> >> struct landlock_ruleset * >> -landlock_create_ruleset(const access_mask_t access_mask); >> +landlock_create_ruleset(const access_mask_t access_mask_fs, >> + const access_mask_t access_mask_net); >> >> void landlock_put_ruleset(struct landlock_ruleset *const ruleset); >> void landlock_put_ruleset_deferred(struct landlock_ruleset *const ruleset); >> @@ -226,6 +238,21 @@ landlock_add_fs_access_mask(struct landlock_ruleset *const ruleset, >> (fs_mask << LANDLOCK_SHIFT_ACCESS_FS); >> } >> >> +/* A helper function to set a network mask. */ > > I already said that this comment is useless, and I removed it in my > patch. Please take a closer look at reviews. Sorry. I missed that in your patch. Will be fixed. > > >> +static inline void >> +landlock_add_net_access_mask(struct landlock_ruleset *const ruleset, >> + const access_mask_t net_access_mask, >> + const u16 layer_level) >> +{ >> + access_mask_t net_mask = net_access_mask & LANDLOCK_MASK_ACCESS_NET; >> + >> + /* Should already be checked in sys_landlock_create_ruleset(). */ >> + WARN_ON_ONCE(net_access_mask != net_mask); >> + // TODO: Add tests to check "|=" and not "=" >> + ruleset->access_masks[layer_level] |= >> + (net_mask << LANDLOCK_SHIFT_ACCESS_NET); >> +} >> + >> /* A helper function to get a filesystem mask. */ >> static inline access_mask_t >> landlock_get_fs_access_mask(const struct landlock_ruleset *const ruleset, >> @@ -236,6 +263,16 @@ landlock_get_fs_access_mask(const struct landlock_ruleset *const ruleset, >> LANDLOCK_MASK_ACCESS_FS; >> } >> >> +/* A helper function to get a network mask. */ >> +static inline access_mask_t >> +landlock_get_net_access_mask(const struct landlock_ruleset *const ruleset, >> + const u16 layer_level) >> +{ >> + return (ruleset->access_masks[layer_level] >> >> + LANDLOCK_SHIFT_ACCESS_NET) & >> + LANDLOCK_MASK_ACCESS_NET; >> +} >> + > > This hunk doesn't match my patch. Do you mean landlock_get_net_access_mask? If yes, there is no diff with your patch here. > > >> bool unmask_layers(const struct landlock_rule *const rule, >> const access_mask_t access_request, >> layer_mask_t (*const layer_masks)[], >> diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c >> index ffd5805eddd9..641155f6f6f8 100644 >> --- a/security/landlock/syscalls.c >> +++ b/security/landlock/syscalls.c >> @@ -189,8 +189,14 @@ SYSCALL_DEFINE3(landlock_create_ruleset, >> LANDLOCK_MASK_ACCESS_FS) >> return -EINVAL; >> >> + /* Checks network content (and 32-bits cast). */ >> + if ((ruleset_attr.handled_access_net | LANDLOCK_MASK_ACCESS_NET) != >> + LANDLOCK_MASK_ACCESS_NET) >> + return -EINVAL; >> + >> /* Checks arguments and transforms to kernel struct. */ >> - ruleset = landlock_create_ruleset(ruleset_attr.handled_access_fs); >> + ruleset = landlock_create_ruleset(ruleset_attr.handled_access_fs, >> + ruleset_attr.handled_access_net); >> if (IS_ERR(ruleset)) >> return PTR_ERR(ruleset); >> >> -- >> 2.25.1 >> > .