From patchwork Fri Apr 19 00:44:50 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Casey Schaufler X-Patchwork-Id: 10908275 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E378818FD for ; Fri, 19 Apr 2019 00:46:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CDAEF28B8F for ; Fri, 19 Apr 2019 00:46:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C25EA28B9F; Fri, 19 Apr 2019 00:46:33 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F14D228B9C for ; Fri, 19 Apr 2019 00:46:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725939AbfDSAqc (ORCPT ); Thu, 18 Apr 2019 20:46:32 -0400 Received: from sonic308-9.consmr.mail.bf2.yahoo.com ([74.6.130.48]:39557 "EHLO sonic308-9.consmr.mail.bf2.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726659AbfDSAqc (ORCPT ); Thu, 18 Apr 2019 20:46:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1555634789; bh=dF+9lBJ8wYV5xYvHfxtglumJAG1aS1bgW4kXIJ5xz2c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From:Subject; b=SC/qhHCEwSyHN2gokpCHWugVqh8YzGzvUJ65+G2RkC/A9I9vCX/Z+XTIDEf7DMvuuEf+xEXT8tpmvUaV0QH6A14xjQkNKXuwaT8IEmggr4YCnJZEVNKBbYh9EdQ09d1gvDld1TqRqWmkzC+FGkxRlEc+p2/A1UF3Z5e4eZAFNDqi6SmfTh2oJOTNJ7DVyIdptEQd2AS7ot4uuX4229P4+ZzoogqCsOzZv46tOCZzszRNDa31FY97EbSVSDo6izZn24j6Tev/kaquTBjdCWjgx5Y9tx/MAS/UypKss9higyDItss54/wyBV30rAfboLpNVNEtlKHV2i8+n3sObPZ59g== X-YMail-OSG: .iBumtEVM1kdV6mqAkM.wznztDR3BW1YOtDdLS1ZBDF8XrzF_7aBhiQfAKUv_al 9mGX925HfYBWxNr8H5JTq1yDrzNP_i5XMymE_LmJzdzbqkXrqDWX74pqsg_Fu2lCj4M5k2qed6BQ 8U7hniFBTB60WVtgwQEt73eSlo_EBhGhDQVx1gCItGd6dqrsu_y6BqPtqcohS1GKXJ5u634I_nHE IWADKBeQWRmOJNzeiy3Oi6hrls2mkx3CzMelZwi5yOerYyZGBn4kBiLR8wJIzO1LZNfIFn99Kk.U yCzsYEq7dNYzhxwQupTBAUu1bkACF192wlMKolOeYOsZ9hl46tuA8FlkXyNGTHr6FdO68wQv_2ew uwb8WpXFXB.v0vWnnramPd5_DYgZg4jy8yUSxZG_P91RCQ2MN7N2uPzrC5c2Hjgwn2n_yd3u8v3W nsOYNjIeSEGKspxMkykDXjUcEv6Id_mxSjxwEDFljTWwr4IEdiYC7RCf.x.O81I_1CRmMtNWeY70 o_Olqkzz.8XW7swtz2iBD6kIY10j46x.Znzfv9YXhlx5n1NFfZsse5wQI3v8dbc9U4zbZruQhPi3 1y2qtfWH0aJ3__is5S6uIqU8YOralUBoBgKKhnCd.swKhGA_s6jtHgCKgKX4QtXjP7Hs.dCaVkZa 8qiBXgWcSslNSUI0I9BQp5tr0Z6usBsnR.xHVE.FeZfmWvXtJBT4Tt1SGHOgo37MR_W4FIJ7OOMk G406gl.6S.PAGHcJRImetMkrQxuaVQbDwJmpoAN0TnGC3.iNrdYkheR5rIH6RbhawN5F3UWHgDqo KLpHwylEKMfWkTItfOn_PZI60Gb3ukia4UwwnrWjT3pirCP1WmNOOGQ_z.Vtbr0fwoVmsOIwFpRF cdsC9qvWkHar8_829MM_dzZEFBhTKyXKdloOMqzjiQ8YCme3kg6GEJ_HNrxI48ZYNfThRTF2bCXD OQbUX80Ih7sq63MpVsMOx4AKlXmumMY7zCiZV.XpYoxcNPxDeaFSPt5ssj7R86QyBgiJs7ub7eYx x8NVBgGIlcAcYr6CBvZVVPhXp7_Jn7A6eeZrPPSSRd.t2xsJOI40HmhchLBg6x5e6qhM37I_V_F_ HYoQn5FyAy.bv7f_w9clS3grOaLN1VjGbcenJFcyhBn7cyN71SQN9d.rlZIa7aQcBdSQrYcMaHk2 bbixw1n1a Received: from sonic.gate.mail.ne1.yahoo.com by sonic308.consmr.mail.bf2.yahoo.com with HTTP; Fri, 19 Apr 2019 00:46:29 +0000 Received: from c-67-169-65-224.hsd1.ca.comcast.net (EHLO localhost.localdomain) ([67.169.65.224]) by smtp431.mail.bf1.yahoo.com (Oath Hermes SMTP Server) with ESMTPA ID cf1bd369acc816a9d15b1740f4265439; Fri, 19 Apr 2019 00:46:27 +0000 (UTC) From: Casey Schaufler To: casey.schaufler@intel.com, jmorris@namei.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org Cc: casey@schaufler-ca.com Subject: [PATCH 03/90] LSM: Infrastructure management of the key security blob Date: Thu, 18 Apr 2019 17:44:50 -0700 Message-Id: <20190419004617.64627-4-casey@schaufler-ca.com> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20190419004617.64627-1-casey@schaufler-ca.com> References: <20190419004617.64627-1-casey@schaufler-ca.com> Sender: selinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Casey Schaufler Move management of the key->security blob out of the individual security modules and into the security infrastructure. Instead of allocating the blobs from within the modules the modules tell the infrastructure how much space is required, and the space is allocated there. Signed-off-by: Casey Schaufler --- include/linux/lsm_hooks.h | 1 + security/security.c | 40 ++++++++++++++++++++++++++++++- security/selinux/hooks.c | 23 +++++------------- security/selinux/include/objsec.h | 7 ++++++ security/smack/smack.h | 7 ++++++ security/smack/smack_lsm.c | 33 ++++++++++++------------- 6 files changed, 75 insertions(+), 36 deletions(-) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 1dbed888dab0..9e3d593a1ec3 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -2058,6 +2058,7 @@ struct lsm_blob_sizes { int lbs_sock; int lbs_superblock; int lbs_ipc; + int lbs_key; int lbs_msg_msg; int lbs_task; }; diff --git a/security/security.c b/security/security.c index e32b7180282e..d05f00a40e82 100644 --- a/security/security.c +++ b/security/security.c @@ -172,6 +172,9 @@ static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed) blob_sizes.lbs_inode = sizeof(struct rcu_head); lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode); lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc); +#ifdef CONFIG_KEYS + lsm_set_blob_size(&needed->lbs_key, &blob_sizes.lbs_key); +#endif lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg); lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock); lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock); @@ -307,6 +310,9 @@ static void __init ordered_lsm_init(void) init_debug("file blob size = %d\n", blob_sizes.lbs_file); init_debug("inode blob size = %d\n", blob_sizes.lbs_inode); init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc); +#ifdef CONFIG_KEYS + init_debug("key blob size = %d\n", blob_sizes.lbs_key); +#endif /* CONFIG_KEYS */ init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); init_debug("sock blob size = %d\n", blob_sizes.lbs_sock); init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock); @@ -573,6 +579,29 @@ static int lsm_ipc_alloc(struct kern_ipc_perm *kip) return 0; } +#ifdef CONFIG_KEYS +/** + * lsm_key_alloc - allocate a composite key blob + * @key: the key that needs a blob + * + * Allocate the key blob for all the modules + * + * Returns 0, or -ENOMEM if memory can't be allocated. + */ +int lsm_key_alloc(struct key *key) +{ + if (blob_sizes.lbs_key == 0) { + key->security = NULL; + return 0; + } + + key->security = kzalloc(blob_sizes.lbs_key, GFP_KERNEL); + if (key->security == NULL) + return -ENOMEM; + return 0; +} +#endif /* CONFIG_KEYS */ + /** * lsm_msg_msg_alloc - allocate a composite msg_msg blob * @mp: the msg_msg that needs a blob @@ -2339,12 +2368,21 @@ EXPORT_SYMBOL(security_skb_classify_flow); int security_key_alloc(struct key *key, const struct cred *cred, unsigned long flags) { - return call_int_hook(key_alloc, 0, key, cred, flags); + int rc = lsm_key_alloc(key); + + if (unlikely(rc)) + return rc; + rc = call_int_hook(key_alloc, 0, key, cred, flags); + if (unlikely(rc)) + security_key_free(key); + return rc; } void security_key_free(struct key *key) { call_void_hook(key_free, key); + kfree(key->security); + key->security = NULL; } int security_key_permission(key_ref_t key_ref, diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index f38a6f484613..ee840fecfebb 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6353,11 +6353,7 @@ static int selinux_key_alloc(struct key *k, const struct cred *cred, unsigned long flags) { const struct task_security_struct *tsec; - struct key_security_struct *ksec; - - ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); - if (!ksec) - return -ENOMEM; + struct key_security_struct *ksec = selinux_key(k); tsec = selinux_cred(cred); if (tsec->keycreate_sid) @@ -6365,18 +6361,9 @@ static int selinux_key_alloc(struct key *k, const struct cred *cred, else ksec->sid = tsec->sid; - k->security = ksec; return 0; } -static void selinux_key_free(struct key *k) -{ - struct key_security_struct *ksec = k->security; - - k->security = NULL; - kfree(ksec); -} - static int selinux_key_permission(key_ref_t key_ref, const struct cred *cred, unsigned perm) @@ -6394,7 +6381,7 @@ static int selinux_key_permission(key_ref_t key_ref, sid = cred_sid(cred); key = key_ref_to_ptr(key_ref); - ksec = key->security; + ksec = selinux_key(key); return avc_has_perm(&selinux_state, sid, ksec->sid, SECCLASS_KEY, perm, NULL); @@ -6402,7 +6389,7 @@ static int selinux_key_permission(key_ref_t key_ref, static int selinux_key_getsecurity(struct key *key, char **_buffer) { - struct key_security_struct *ksec = key->security; + struct key_security_struct *ksec = selinux_key(key); char *context = NULL; unsigned len; int rc; @@ -6627,6 +6614,9 @@ struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = { .lbs_file = sizeof(struct file_security_struct), .lbs_inode = sizeof(struct inode_security_struct), .lbs_ipc = sizeof(struct ipc_security_struct), +#ifdef CONFIG_KEYS + .lbs_key = sizeof(struct key_security_struct), +#endif /* CONFIG_KEYS */ .lbs_msg_msg = sizeof(struct msg_security_struct), .lbs_sock = sizeof(struct sk_security_struct), .lbs_superblock = sizeof(struct superblock_security_struct), @@ -6842,7 +6832,6 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { #ifdef CONFIG_KEYS LSM_HOOK_INIT(key_alloc, selinux_key_alloc), - LSM_HOOK_INIT(key_free, selinux_key_free), LSM_HOOK_INIT(key_permission, selinux_key_permission), LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), #endif diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h index 29f02b8f8f31..3b78aa4ee98f 100644 --- a/security/selinux/include/objsec.h +++ b/security/selinux/include/objsec.h @@ -194,6 +194,13 @@ static inline struct superblock_security_struct *selinux_superblock( return superblock->s_security + selinux_blob_sizes.lbs_superblock; } +#ifdef CONFIG_KEYS +static inline struct key_security_struct *selinux_key(const struct key *key) +{ + return key->security + selinux_blob_sizes.lbs_key; +} +#endif /* CONFIG_KEYS */ + static inline struct sk_security_struct *selinux_sock(const struct sock *sock) { return sock->sk_security + selinux_blob_sizes.lbs_sock; diff --git a/security/smack/smack.h b/security/smack/smack.h index 4ac4bf3310d7..7cc3a3382fee 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -386,6 +386,13 @@ static inline struct superblock_smack *smack_superblock( return superblock->s_security + smack_blob_sizes.lbs_superblock; } +#ifdef CONFIG_KEYS +static inline struct smack_known **smack_key(const struct key *key) +{ + return key->security + smack_blob_sizes.lbs_key; +} +#endif /* CONFIG_KEYS */ + /* * Is the directory transmuting? */ diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index fd69e1bd841b..e9560b078efe 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -4179,23 +4179,13 @@ static void smack_inet_csk_clone(struct sock *sk, static int smack_key_alloc(struct key *key, const struct cred *cred, unsigned long flags) { + struct smack_known **blob = smack_key(key); struct smack_known *skp = smk_of_task(smack_cred(cred)); - key->security = skp; + *blob = skp; return 0; } -/** - * smack_key_free - Clear the key security blob - * @key: the object - * - * Clear the blob pointer - */ -static void smack_key_free(struct key *key) -{ - key->security = NULL; -} - /** * smack_key_permission - Smack access on a key * @key_ref: gets to the object @@ -4208,6 +4198,8 @@ static void smack_key_free(struct key *key) static int smack_key_permission(key_ref_t key_ref, const struct cred *cred, unsigned perm) { + struct smack_known **blob; + struct smack_known *skp; struct key *keyp; struct smk_audit_info ad; struct smack_known *tkp = smk_of_task(smack_cred(cred)); @@ -4227,7 +4219,9 @@ static int smack_key_permission(key_ref_t key_ref, * If the key hasn't been initialized give it access so that * it may do so. */ - if (keyp->security == NULL) + blob = smack_key(keyp); + skp = *blob; + if (skp == NULL) return 0; /* * This should not occur @@ -4247,8 +4241,8 @@ static int smack_key_permission(key_ref_t key_ref, request |= MAY_READ; if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR)) request |= MAY_WRITE; - rc = smk_access(tkp, keyp->security, request, &ad); - rc = smk_bu_note("key access", tkp, keyp->security, request, rc); + rc = smk_access(tkp, skp, request, &ad); + rc = smk_bu_note("key access", tkp, skp, request, rc); return rc; } @@ -4263,11 +4257,12 @@ static int smack_key_permission(key_ref_t key_ref, */ static int smack_key_getsecurity(struct key *key, char **_buffer) { - struct smack_known *skp = key->security; + struct smack_known **blob = smack_key(key); + struct smack_known *skp = *blob; size_t length; char *copy; - if (key->security == NULL) { + if (skp == NULL) { *_buffer = NULL; return 0; } @@ -4550,6 +4545,9 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = { .lbs_file = sizeof(struct smack_known *), .lbs_inode = sizeof(struct inode_smack), .lbs_ipc = sizeof(struct smack_known *), +#ifdef CONFIG_KEYS + .lbs_key = sizeof(struct smack_known *), +#endif /* CONFIG_KEYS */ .lbs_msg_msg = sizeof(struct smack_known *), .lbs_sock = sizeof(struct socket_smack), .lbs_superblock = sizeof(struct superblock_smack), @@ -4671,7 +4669,6 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = { /* key management security hooks */ #ifdef CONFIG_KEYS LSM_HOOK_INIT(key_alloc, smack_key_alloc), - LSM_HOOK_INIT(key_free, smack_key_free), LSM_HOOK_INIT(key_permission, smack_key_permission), LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity), #endif /* CONFIG_KEYS */