From patchwork Thu Jul 14 22:56:45 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Jurgens X-Patchwork-Id: 9230833 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 834406075D for ; Thu, 14 Jul 2016 22:57:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 793C227F94 for ; Thu, 14 Jul 2016 22:57:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6C74E281B7; Thu, 14 Jul 2016 22:57:40 +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, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY 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 CA1E127F94 for ; Thu, 14 Jul 2016 22:57:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752011AbcGNW5j (ORCPT ); Thu, 14 Jul 2016 18:57:39 -0400 Received: from mail-il-dmz.mellanox.com ([193.47.165.129]:35829 "EHLO mellanox.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751246AbcGNW5i (ORCPT ); Thu, 14 Jul 2016 18:57:38 -0400 Received: from Internal Mail-Server by MTLPINE1 (envelope-from danielj@mellanox.com) with ESMTPS (AES256-SHA encrypted); 15 Jul 2016 01:57:36 +0300 Received: from x-vnc01.mtx.labs.mlnx (x-vnc01.mtx.labs.mlnx [10.12.150.16]) by labmailer.mlnx (8.13.8/8.13.8) with ESMTP id u6EMv9u4030854; Fri, 15 Jul 2016 01:57:32 +0300 From: Dan Jurgens To: chrisw@sous-sol.org, paul@paul-moore.com, sds@tycho.nsa.gov, eparis@parisplace.org, dledford@redhat.com, sean.hefty@intel.com, hal.rosenstock@gmail.com Cc: selinux@tycho.nsa.gov, linux-security-module@vger.kernel.org, linux-rdma@vger.kernel.org, yevgenyp@mellanox.com, Daniel Jurgens Subject: [PATCH v2 3/9] selinux lsm IB/core: Implement LSM notification system Date: Fri, 15 Jul 2016 01:56:45 +0300 Message-Id: <1468537011-20407-4-git-send-email-danielj@mellanox.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1468537011-20407-1-git-send-email-danielj@mellanox.com> References: <1468537011-20407-1-git-send-email-danielj@mellanox.com> Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP From: Daniel Jurgens Add a generic notificaiton mechanism in the LSM. Interested consumers can register a callback with the LSM and security modules can produce events. Because access to Infiniband QPs are enforced in the setup phase of a connection security should be enforced again if the policy changes. Register infiniband devices for policy change notification and check all QPs on that device when the notification is received. Add a call to the notification mechanism is from SELinux when the AVC cache changes. Signed-off-by: Daniel Jurgens --- v2: - new patch that has the generic notification, replaces selinux and IB/core patches related to the ib_flush callback. Yuval Shaia and Paul Moore --- drivers/infiniband/core/device.c | 46 ++++++++++++++++++++++++++++++ include/linux/security.h | 10 ++++++ security/security.c | 58 ++++++++++++++++++++++++++++++++++++++ security/selinux/hooks.c | 5 ++- security/selinux/selinuxfs.c | 2 + 5 files changed, 119 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c index 5b42e83..3219a7a 100644 --- a/drivers/infiniband/core/device.c +++ b/drivers/infiniband/core/device.c @@ -39,6 +39,7 @@ #include #include #include +#include #include #include #include @@ -82,6 +83,10 @@ static LIST_HEAD(client_list); static DEFINE_MUTEX(device_mutex); static DECLARE_RWSEM(lists_rwsem); +static void ib_policy_change_task(struct work_struct *work); +static DECLARE_WORK(ib_policy_change_work, ib_policy_change_task); + +static u32 lsm_callback_id; static int ib_device_check_mandatory(struct ib_device *device) { @@ -344,6 +349,37 @@ static int setup_port_pkey_list(struct ib_device *device) return 0; } +static void ib_policy_change_task(struct work_struct *work) +{ + struct ib_device *dev; + + down_read(&lists_rwsem); + list_for_each_entry(dev, &device_list, core_list) { + int i; + + for (i = rdma_start_port(dev); i <= rdma_end_port(dev); i++) { + u64 sp; + int ret = ib_get_cached_subnet_prefix(dev, + i, + &sp); + + WARN_ONCE(ret, + "ib_get_cached_subnet_prefix err: %d, this should never happen here\n", + ret); + ib_security_cache_change(dev, i, sp); + } + } + up_read(&lists_rwsem); +} + +static void ib_security_change(enum lsm_event event, void *ctx, void *lsm_data) +{ + if (event != LSM_POLICY_CHANGE) + return; + + schedule_work(&ib_policy_change_work); +} + /** * ib_register_device - Register an IB device with IB core * @device:Device to register @@ -1075,10 +1111,19 @@ static int __init ib_core_init(void) goto err_sa; } + ret = security_register_lsm_notifier(&ib_security_change, NULL, + &lsm_callback_id); + if (ret) { + pr_warn("Couldn't register LSM notifier. ret %d\n", ret); + goto err_ibnl_clients; + } + ib_cache_setup(); return 0; +err_ibnl_clients: + ib_remove_ibnl_clients(); err_sa: ib_sa_cleanup(); err_mad: @@ -1098,6 +1143,7 @@ err: static void __exit ib_core_cleanup(void) { + security_unregister_lsm_notifier(lsm_callback_id); ib_cache_cleanup(); ib_remove_ibnl_clients(); ib_sa_cleanup(); diff --git a/include/linux/security.h b/include/linux/security.h index 33e23c4..bf53911 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -69,6 +69,16 @@ struct audit_krule; struct user_namespace; struct timezone; +enum lsm_event { + LSM_POLICY_CHANGE, +}; + +typedef void (*lsm_notifier)(enum lsm_event event, void *ctx, void *data); + +void security_lsm_notify(enum lsm_event event, void *data); +int security_register_lsm_notifier(lsm_notifier func, void *ctx, u32 *id); +void security_unregister_lsm_notifier(u32 id); + /* These functions are in security/commoncap.c */ extern int cap_capable(const struct cred *cred, struct user_namespace *ns, int cap, int audit); diff --git a/security/security.c b/security/security.c index 234982d..1263c1d 100644 --- a/security/security.c +++ b/security/security.c @@ -33,6 +33,18 @@ /* Maximum number of letters for an LSM name string */ #define SECURITY_NAME_MAX 10 +struct lsm_notifier_entry { + u32 callback_id; + lsm_notifier func; + void *ctx; + struct list_head list; + struct rcu_head rcu; +}; + +static LIST_HEAD(lsm_notifier_list); +static DEFINE_SPINLOCK(lsm_notifier_lock); +static u32 next_callback_id; + /* Boot-time LSM user choice */ static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] = CONFIG_DEFAULT_SECURITY; @@ -98,6 +110,52 @@ int __init security_module_enable(const char *module) return !strcmp(module, chosen_lsm); } +void security_lsm_notify(enum lsm_event event, void *data) +{ + struct lsm_notifier_entry *entry; + + rcu_read_lock(); + list_for_each_entry_rcu(entry, &lsm_notifier_list, list) + entry->func(event, entry->ctx, data); + rcu_read_unlock(); +} +EXPORT_SYMBOL(security_lsm_notify); + +int security_register_lsm_notifier(lsm_notifier func, void *ctx, u32 *id) +{ + struct lsm_notifier_entry *entry; + + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + + entry->func = func; + entry->ctx = ctx; + + spin_lock(&lsm_notifier_lock); + entry->callback_id = next_callback_id++; + *id = entry->callback_id; + list_add_rcu(&entry->list, &lsm_notifier_list); + spin_unlock(&lsm_notifier_lock); + + return 0; +} +EXPORT_SYMBOL(security_register_lsm_notifier); + +void security_unregister_lsm_notifier(u32 id) +{ + struct lsm_notifier_entry *entry; + + list_for_each_entry_rcu(entry, &lsm_notifier_list, list) { + if (entry->callback_id == id) { + list_del_rcu(&entry->list); + kfree_rcu(entry, rcu); + break; + } + } +} +EXPORT_SYMBOL(security_unregister_lsm_notifier); + /* * Hook list operation macros. * diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index a86d537..a363202 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -159,13 +159,14 @@ static int selinux_peerlbl_enabled(void) return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); } -static int selinux_netcache_avc_callback(u32 event) +static int selinux_cache_avc_callback(u32 event) { if (event == AVC_CALLBACK_RESET) { sel_netif_flush(); sel_netnode_flush(); sel_netport_flush(); synchronize_net(); + security_lsm_notify(LSM_POLICY_CHANGE, NULL); } return 0; } @@ -6235,7 +6236,7 @@ static __init int selinux_init(void) security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); - if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) + if (avc_add_callback(selinux_cache_avc_callback, AVC_CALLBACK_RESET)) panic("SELinux: Unable to register AVC netcache callback\n"); if (selinux_enforcing) diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 1b1fd27..adc09e7 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -177,6 +177,8 @@ static ssize_t sel_write_enforce(struct file *file, const char __user *buf, avc_ss_reset(0); selnl_notify_setenforce(selinux_enforcing); selinux_status_update_setenforce(selinux_enforcing); + if (!selinux_enforcing) + security_lsm_notify(LSM_POLICY_CHANGE, NULL); } length = count; out: