From patchwork Sun Jun 2 16:50:06 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Casey Schaufler X-Patchwork-Id: 10971801 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 87EB317DF for ; Sun, 2 Jun 2019 16:51:14 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7439B286E4 for ; Sun, 2 Jun 2019 16:51:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 685E328A00; Sun, 2 Jun 2019 16:51:14 +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 71AE028703 for ; Sun, 2 Jun 2019 16:51:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726695AbfFBQvN (ORCPT ); Sun, 2 Jun 2019 12:51:13 -0400 Received: from sonic302-8.consmr.mail.bf2.yahoo.com ([74.6.135.47]:38396 "EHLO sonic302-8.consmr.mail.bf2.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726842AbfFBQvN (ORCPT ); Sun, 2 Jun 2019 12:51:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1559494270; bh=VQcY1jMogEANGokqkFaahvbp5o1kvY60QgKEtZZcIo8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From:Subject; b=HWEl2iA699e+qqYXArsJoJ+7xyvsSZp1zsek7JhGoTSsC8ZI//wY/eTxJHtd+UnADo4Q7YRL1PAV+n/SFmjGKSl96JiEdNk5d2yluNFbX4+5fGyUoZ8gXtwJ2/lNtJaBi0zpKv2eLeNX2JUFWyCUtYLvtZJ65ntnU/9+2Mf9vx+j8tkZBU9+VaaZdCcaN5t9yUVogxTvyW5q04MR9f0g/YvGms3TLGq3y9JRK6eeedPNRDO9w0jgGZqJDqWTkA7O6+a9Jz5tkhW8xPgjnkHaYQWmOkzWz8E5aLeP1Zr0QQioxkT9UCFbJJbYAFzggJTzIx5v4os5t66IDgpu38KDRA== X-YMail-OSG: ir4SJRoVM1nUHOvBhD2_gDAsatNY_V_mY2s7xw9jwsZlC8uJlglJdizolBfvJ1V xS7n5LXaLWnClNWgbg5gklb5Y2YwhtOBVfZz0XgdWGngWP9CabO3vu2yHrIKgDLb5SnMoHPS5YpD xTtJOq2ZjQfZ_gTeTxSGyrf0Hg.ZayXK._sGYc9_UmUfgl6Hvr1Y6fE.Bg0ph2d2tsBIbiIBxX1z xJcIFOdu_UqZqsVHKkP27eeMa3B4NZ4SYC9EY7kq9_J4mY8sIXRmhtd8xFyoJPr3nyAuBc2EgB5i PRACG.SfnaqBD7mGi7FocKhFsIgSa7mFEjz7MEixsOj2Y4P6HG_cNYVamdtpRwLcOgi2hlWjqp0W k_xrlEpOOYI_LOZgKQrWO2oNCFej2sHP28QBagTVdhdBDBVNV.1DU7E8JfvTHmH.ByH_It4aEB9c wsbDyCjXuLitp7ujprL2oUMYVoazRjZC94.MqJqwQ.pShkJwVtL3VweLWkftkfCLR4F5f7jvMSDn gEXpTUnekWR0JaR9vsRYlhaDnDsBZrRDaDOee8.p0zQOloOtx4wPiZWHhfdEW0Ss4UDc5aLWqY5n AphbPVKux_BOq6Zw6IqTUarYtE19p4y4Lb8tbjCTYtzBPUznFkR3ubolEEJ6aeg_DXqVGhfVZra_ Ono3Ganwz0f8bX3hySL6K7nCqhzaLmPGAAbeO4jPZZGabeuGYxYDtgrKRr0imLxRX4fBSZJjpG4U Mr9mD1BHenyOohkBS0izKetYTrIC_dKFrlFAz93nKmtPHm1T6pbW93XfjHL6q.EG.zOvE1xzx30s qysqW3edVe407rJYoIg087ztYO6lolyt4EqxypABq5hMjyW8rvxH2IIJ1RrQiqQalTQXDEvnYEJV zHRSEz2zHPy9vomRNAs_m_vUp2Ria2nQDxVzv4x_oQ40QWOvSUzLBC4pcPPUqxN79ydPHLP1WgF2 Q1m6F8C9FkRoJGbIz9ueIn1B0rmZiiACZegjtqPK3k3nNfnciNVNEgXgiwGtw._ykUOTbaLPdbT_ jg4.zuaX_VeYATdJmO61MbPSaM3Ez4DDWqNELhetZsqx8tQTPl0vVjXtm6pm83B2G7LcM0C6dAMo SlLV_j9JLko4vy_QKOkc3DsCQuontL1qwHXHg5ueLemXsqWT9FnMXtEKMVwQAW6yvFp61EbJS9L8 L_7AE7NoicdDxc.PB80HRLCrhKKoZT.uuU9v.znOGTYbZrRl8_AiBnpN5MPDm5oOrCoD2xhTGuOm GXx8nz4B4JOjSR0a7h9nZDUkoelfDWb9dmoc8iEu8Lwi8Mw-- Received: from sonic.gate.mail.ne1.yahoo.com by sonic302.consmr.mail.bf2.yahoo.com with HTTP; Sun, 2 Jun 2019 16:51:10 +0000 Received: from c-73-223-4-185.hsd1.ca.comcast.net (EHLO localhost.net) ([73.223.4.185]) by smtp429.mail.bf1.yahoo.com (Oath Hermes SMTP Server) with ESMTPA ID 844f659d1e234107537a664739855744; Sun, 02 Jun 2019 16:51:09 +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: Sun, 2 Jun 2019 09:50:06 -0700 Message-Id: <20190602165101.25079-4-casey@schaufler-ca.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190602165101.25079-1-casey@schaufler-ca.com> References: <20190602165101.25079-1-casey@schaufler-ca.com> MIME-Version: 1.0 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 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 */