From patchwork Fri May 31 23:30:54 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Casey Schaufler X-Patchwork-Id: 10970991 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 7E8C36C5 for ; Fri, 31 May 2019 23:32:13 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6D23528D9E for ; Fri, 31 May 2019 23:32:13 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5FD0928DA3; Fri, 31 May 2019 23:32:13 +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=-6.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,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 8C4E428D9E for ; Fri, 31 May 2019 23:32:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726610AbfEaXcM (ORCPT ); Fri, 31 May 2019 19:32:12 -0400 Received: from sonic316-13.consmr.mail.gq1.yahoo.com ([98.137.69.37]:43197 "EHLO sonic316-13.consmr.mail.gq1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726555AbfEaXcM (ORCPT ); Fri, 31 May 2019 19:32:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1559345530; bh=VQcY1jMogEANGokqkFaahvbp5o1kvY60QgKEtZZcIo8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From:Subject; b=Z1fbS6/6Ls6Sd2azG/RZpr9MRwaYdADT2x/KQz70mZpei+yON+9nRCoWDfoj90q5FcrloH66lbnCXpDZGR/meuU70VdF6mrF6jmjGSKwqGG40OBmkLuEf8PQ9qfkj7p20JbLr+NzkqBz/i8cYtvqa6JjH4dS6oio2nfc5JoEHI53G+/4+NhDrKTvYsZJX7z/1xC/Ui2B4gUiJ8o3T/LrUZi4cLd6fP1xb3F/jwGzWqSx907A5Dirh+djOXzROGSGzkwZYHGXD5EEyxXshvQuj/OFX7MkQThQOCFzelNJAN+dPhAnLDdzKU3K2v1fxhjO01yWQRaXg73a5vIZ1kjfzw== X-YMail-OSG: XhGFtO8VM1lOPmLCAGi58pf1y0TrzBZCgjT7Vjqp._NF37PcWvB5yu7SLr5.0Ly 1P3cf1WM38FunTdXryvtyVM7UNWZDJdsfZUc.O1Q76rahUK7mvwt5Hmpx8.Anq1wm_KvM40O9zp7 iU9jXRn12PlnTjriJU_EqtnTLPVvz2g.hoR.jDbbd6Lr.U13v1k.fo6GYFVZsS5l4lhjfGvYN1Tl OJnSyRqjzrzpGSsgZs3d.T01SHYalT5Zb7qNMD9xTFztRR7JE_7e27QfBmeUq7qSWPbonq0PDYyZ DZzwmcE.cygvF9MVdBPwnYeaNRd44SwxrmRlyjAA8w_6MvrUBTbf7V81l9FJ6mPY2BLhrfzC.QXA aB0.V5AUFB33yebPs9rKOLKwUJ0GLIYu3LIVag2pGjsn0h8.yYKkEYPGkE150g.YM.tCSuX4gYT6 XwuZevIHzQVUTmiMqdXqyzdOd12T.d4d4IvltdxWbhht3rxbiatVzol9QiJoKF6D7H8hb22g3OiG A9oCmx.pvJuKHwHS.pnECjwk0xhM3NnBIa9mbgCbCYDDab98KVtCUBYI4z3DqfysjMadrlOdSyhI 5DjAYBL_Nr3Z6P73cg_9E2ErZ.fFwdhaXa2pNGctK0Csa_HlVopEOLcOXX1PxGuCDvK7A7Dh_b9S 2NJ6WZ.b2rnMzV4tHN1wWho0ojlSZYrgZRcj3oYddP6PtHCCtRiVH2pRBjE_R_nhq_8fCPJY4Wsz 9J9FHan4WrEtavczfK0BiZg3cexUmGyf1NKHKx.icynHGbYDSNac9wOrxsbugZ9tjmm1e2rbh51I 9FcnnpxqUYvuQCfjy9_hoblo1Rrf82U7c1fT61OxAOSkMRyHrUSbNvqmKD7HksuZXliXs2UF2oOJ v.TgbU6Ckzeo2rLLcgzmns3TXY.OKaqRi5VoBDB2qmKGdcfyHG.jh2.vcRkHciIO896.4GpySJ0e NJk3lGPevp7ILn2.UE2aBNKjgqX5cCgNTcZ3__reY.efdV4lbNXJmUjN_Ddx068qOw.ollLLX5il yvympPMo4eOtW5umcv1c5w5qIIyPAv3ehepkYkg8VV6PfG.KVwC4zdQh90FIw4g4eCaIpjurw3M7 9sEudXKrwZKqMeVIyE233rgeh4vMHqqyeqNxbQ_8r0ke.yPr3ICs68Uh_QScx6fW0VtWjOComNbR jNd2wQnU6HomdJu1pmVLkDV167zAgbdy9J6C2J3MvPAlnE82DyKDC_KS8iAQ7Wx1571HakxdIlru hoMEhEPxVlGFCnkgomSlQY.TeaqgUMOyVYf_yKs_kTp0.j8OQpfCMvg-- Received: from sonic.gate.mail.ne1.yahoo.com by sonic316.consmr.mail.gq1.yahoo.com with HTTP; Fri, 31 May 2019 23:32:10 +0000 Received: from c-73-223-4-185.hsd1.ca.comcast.net (EHLO localhost.localdomain) ([73.223.4.185]) by smtp402.mail.gq1.yahoo.com (Oath Hermes SMTP Server) with ESMTPA ID 675ec5c40bde2b908ed280c0dd17adb5; Fri, 31 May 2019 23:32:09 +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, keescook@chromium.org, john.johansen@canonical.com, penguin-kernel@i-love.sakura.ne.jp, paul@paul-moore.com, sds@tycho.nsa.gov Subject: [PATCH 03/58] LSM: Infrastructure management of the key security blob Date: Fri, 31 May 2019 16:30:54 -0700 Message-Id: <20190531233149.715-4-casey@schaufler-ca.com> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20190531233149.715-1-casey@schaufler-ca.com> References: <20190531233149.715-1-casey@schaufler-ca.com> Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: 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 b353482ea348..3fe39abccc8f 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -2050,6 +2050,7 @@ 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 */