From patchwork Tue Jan 25 22:46:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Berger X-Patchwork-Id: 12724357 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 A7C2CC63686 for ; Tue, 25 Jan 2022 23:09:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234274AbiAYWrm (ORCPT ); Tue, 25 Jan 2022 17:47:42 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:12368 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S234218AbiAYWr2 (ORCPT ); Tue, 25 Jan 2022 17:47:28 -0500 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 20PMh0vw011541; Tue, 25 Jan 2022 22:47:05 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=0vN/OnpNxs2gxrQFo4ydOTrn69NRjrKOtMZh3Q4N+Js=; b=UxL+JZ2+j0oUZEwBpvjx5pPDKUqsQH3ABb658S2Nmlc4YvuqjyGJ2nVcCDT+IWAxpquI CIe+aM+6kTFw9QlskC3dylczHOhrnYSqYIEotJg1No4wKaYxE/kyP/gFMdDkG8AP5jm3 /GuZXLlBi9QtbPfHVQ9Z8od6hDEzorVukG8Ci4PVY+PEXcZQQ0oyWrJZbDi+KdLtfBLp HJbM5/tHMDvuCe/KPLrReNXsMOJyr9cbMW4YeSXIo2K7kKnOX+3DH5+E16PSWzsUY4yx yNq86bo3ubygt09f7gYS4PToJarEPTSwCtlfSsDCD6JuCDBONXmXJ3wmu9c9ThsawTy3 bQ== Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 3dtt83g1v9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 25 Jan 2022 22:47:05 +0000 Received: from m0098416.ppops.net (m0098416.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 20PMhC3H012543; Tue, 25 Jan 2022 22:47:04 GMT Received: from ppma02dal.us.ibm.com (a.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.10]) by mx0b-001b2d01.pphosted.com with ESMTP id 3dtt83g1uy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 25 Jan 2022 22:47:04 +0000 Received: from pps.filterd (ppma02dal.us.ibm.com [127.0.0.1]) by ppma02dal.us.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 20PMh3Mr011257; Tue, 25 Jan 2022 22:47:03 GMT Received: from b01cxnp23034.gho.pok.ibm.com (b01cxnp23034.gho.pok.ibm.com [9.57.198.29]) by ppma02dal.us.ibm.com with ESMTP id 3dt1x9rg8u-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 25 Jan 2022 22:47:03 +0000 Received: from b01ledav006.gho.pok.ibm.com (b01ledav006.gho.pok.ibm.com [9.57.199.111]) by b01cxnp23034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 20PMkxgs31719798 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 25 Jan 2022 22:46:59 GMT Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C47D2AC068; Tue, 25 Jan 2022 22:46:59 +0000 (GMT) Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 93EC1AC05E; Tue, 25 Jan 2022 22:46:59 +0000 (GMT) Received: from sbct-3.pok.ibm.com (unknown [9.47.158.153]) by b01ledav006.gho.pok.ibm.com (Postfix) with ESMTP; Tue, 25 Jan 2022 22:46:59 +0000 (GMT) From: Stefan Berger To: linux-integrity@vger.kernel.org Cc: zohar@linux.ibm.com, serge@hallyn.com, christian.brauner@ubuntu.com, containers@lists.linux.dev, dmitry.kasatkin@gmail.com, ebiederm@xmission.com, krzysztof.struczynski@huawei.com, roberto.sassu@huawei.com, mpeters@redhat.com, lhinds@redhat.com, lsturman@redhat.com, puiterwi@redhat.com, jejb@linux.ibm.com, jamjoom@us.ibm.com, linux-kernel@vger.kernel.org, paul@paul-moore.com, rgb@redhat.com, linux-security-module@vger.kernel.org, jmorris@namei.org, Stefan Berger Subject: [PATCH v9 23/23] ima: Enable IMA namespaces Date: Tue, 25 Jan 2022 17:46:45 -0500 Message-Id: <20220125224645.79319-24-stefanb@linux.vnet.ibm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220125224645.79319-1-stefanb@linux.vnet.ibm.com> References: <20220125224645.79319-1-stefanb@linux.vnet.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: grqyLkGugVKLiWcMKy70l8R11h_vfkiJ X-Proofpoint-GUID: vGO_ywtuqZ0AMPqbdjSjap4nfpVs1T8M X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.816,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2022-01-25_06,2022-01-25_02,2021-12-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 mlxscore=0 phishscore=0 lowpriorityscore=0 spamscore=0 malwarescore=0 adultscore=0 priorityscore=1501 clxscore=1015 bulkscore=0 impostorscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2201110000 definitions=main-2201250135 Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Stefan Berger Introduce the IMA_NS in Kconfig for IMA namespace enablement. Enable the lazy initialization of an IMA namespace when a user mounts SecurityFS and writes '1' into IMA's 'active' securityfs file. A user_namespace will now get a pointer to an ima_namespace and therefore implement get_current_ns() for the namespacing case that returns this pointer. Use get_current_ns() in those places that require access to the current IMA namespace. In some places, primarily those related to IMA-appraisal and changes to file attributes, keep the pointer to init_ima_ns, since there flags related to file measurements may be affected, which are not supported in IMA namespaces, yet. Before using the ima_namespace pointer test it with ns_is_active() to check whether it is NULL and whether the ima_namespace is active. If it's not active, it cannot be used, yet. Therefore, return early from those functions that may now get either get a NULL pointer from this call or where ns->active is still 0. The init_ima_ns is always set to be active, thus passing the check. Implement ima_ns_from_file() for SecurityFS-related files where we can now get the IMA namespace via the user namespace pointer associated with the superblock of the SecurityFS filesystem instance. Return -EACCES to IMA's securityfs files, except for the 'active' file, until the IMA namespace has been set to active. Switch access to userns->ima_ns to use acquire/release semantics to ensure that a newly created ima_namespace structure is fully visible upon access. Only emit the kernel log message 'policy update completed' for the init_ima_ns. Gate access to ima_appraise variable to init_ima_ns in ima_load_data(). Signed-off-by: Stefan Berger --- v9: - ima_post_key_create_or_update: Only handle key if in init_ima_ns - Removed ns == NULL checks where user_namespace is now passed - Defer setting of user_ns->ima_ns until end of ima_fs_ns_init(); required new ima_free_imans() and new user_ns_set_ima_ns() - Only emit log message 'policy update completed' for init_ima_ns - Introduce get_current_ns() only in this patch - Check for ns == &init_ima_ns in ima_load_data() --- include/linux/ima.h | 13 ++++ init/Kconfig | 13 ++++ kernel/user_namespace.c | 2 + security/integrity/ima/ima.h | 51 ++++++++++++-- security/integrity/ima/ima_appraise.c | 3 + security/integrity/ima/ima_asymmetric_keys.c | 6 +- security/integrity/ima/ima_fs.c | 74 ++++++++++++++++---- security/integrity/ima/ima_init_ima_ns.c | 2 + security/integrity/ima/ima_main.c | 35 +++++---- security/integrity/ima/ima_ns.c | 15 ++-- security/integrity/ima/ima_policy.c | 16 +++-- 11 files changed, 188 insertions(+), 42 deletions(-) diff --git a/include/linux/ima.h b/include/linux/ima.h index c584527c0f47..4e595bd9733e 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -11,6 +11,7 @@ #include #include #include +#include #include struct linux_binprm; @@ -68,6 +69,18 @@ static inline const char * const *arch_get_ima_policy(void) } #endif +static inline struct user_namespace +*ima_ns_to_user_ns(struct ima_namespace *ns) +{ + struct user_namespace *user_ns; + + user_ns = current_user_ns(); +#ifdef CONFIG_IMA_NS + WARN_ON(user_ns->ima_ns != ns); +#endif + return user_ns; +} + #else static inline enum hash_algo ima_get_current_hash_algo(void) { diff --git a/init/Kconfig b/init/Kconfig index 4b7bac10c72d..e27155e0ddba 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1247,6 +1247,19 @@ config NET_NS Allow user space to create what appear to be multiple instances of the network stack. +config IMA_NS + bool "IMA namespace" + depends on USER_NS + depends on IMA + default n + help + Allow the creation of an IMA namespace for each user namespace. + Namespaced IMA enables having IMA features work separately + in each IMA namespace. + Currently, only the audit status flags are stored in the namespace, + which allows the same file to be audited each time it is accessed + in a new namespace. + endif # NAMESPACES config CHECKPOINT_RESTORE diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c index 6b2e3ca7ee99..653f8fa83b69 100644 --- a/kernel/user_namespace.c +++ b/kernel/user_namespace.c @@ -20,6 +20,7 @@ #include #include #include +#include static struct kmem_cache *user_ns_cachep __read_mostly; static DEFINE_MUTEX(userns_state_mutex); @@ -196,6 +197,7 @@ static void free_user_ns(struct work_struct *work) kfree(ns->projid_map.forward); kfree(ns->projid_map.reverse); } + free_ima_ns(ns); retire_userns_sysctls(ns); key_free_user_ns(ns); ns_free_inum(&ns->ns); diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index cf2f63bb5bdf..a0dbb1dccc8e 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -536,32 +536,70 @@ struct user_namespace *ima_user_ns_from_file(const struct file *filp) return file_inode(filp)->i_sb->s_user_ns; } +#ifdef CONFIG_IMA_NS + static inline struct ima_namespace *ima_ns_from_user_ns(struct user_namespace *user_ns) { - if (user_ns == &init_user_ns) - return &init_ima_ns; - return NULL; + /* Pairs with smp_store_releases() in user_ns_set_ima_ns(). */ + return smp_load_acquire(&user_ns->ima_ns); } -#ifdef CONFIG_IMA_NS +static inline void user_ns_set_ima_ns(struct user_namespace *user_ns, + struct ima_namespace *ns) +{ + /* Pairs with smp_load_acquire() in ima_ns_from_user_ns() */ + smp_store_release(&user_ns->ima_ns, ns); +} + +static inline struct ima_namespace *get_current_ns(void) +{ + return ima_ns_from_user_ns(current_user_ns()); +} struct ima_namespace *create_ima_ns(void); +void ima_free_ima_ns(struct ima_namespace *ns); + struct ns_status *ima_get_ns_status(struct ima_namespace *ns, struct inode *inode, struct integrity_iint_cache *iint); void ima_free_ns_status_tree(struct ima_namespace *ns); +static inline struct ima_namespace *ima_ns_from_file(const struct file *filp) +{ + return ima_user_ns_from_file(filp)->ima_ns; +} + #else +static inline struct ima_namespace +*ima_ns_from_user_ns(struct user_namespace *user_ns) +{ + if (user_ns == &init_user_ns) + return &init_ima_ns; + return NULL; +} + +static inline void user_ns_set_ima_ns(struct user_namespace *user_ns, + struct ima_namespace *ns) +{ +} + +static inline struct ima_namespace *get_current_ns(void) +{ + return &init_ima_ns; +} + static inline struct ima_namespace *create_ima_ns(void) { WARN(1, "Cannot create an IMA namespace\n"); return ERR_PTR(-EFAULT); } +static inline void ima_free_ima_ns(struct ima_namespace *ns) {} + static inline struct ns_status *ima_get_ns_status(struct ima_namespace *ns, struct inode *inode, struct integrity_iint_cache *iint) @@ -576,6 +614,11 @@ static inline struct ns_status *ima_get_ns_status(struct ima_namespace *ns, return ns_status; } +static inline struct ima_namespace *ima_ns_from_file(const struct file *filp) +{ + return &init_ima_ns; +} + #endif /* CONFIG_IMA_NS */ #endif /* __LINUX_IMA_H */ diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 3461025f671b..2ad3327d7ce6 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -74,6 +74,9 @@ int ima_must_appraise(struct ima_namespace *ns, { u32 secid; + if (ns != &init_ima_ns) + return 0; + if (!ima_appraise) return 0; diff --git a/security/integrity/ima/ima_asymmetric_keys.c b/security/integrity/ima/ima_asymmetric_keys.c index 70d87df26068..0d2cc1e23cde 100644 --- a/security/integrity/ima/ima_asymmetric_keys.c +++ b/security/integrity/ima/ima_asymmetric_keys.c @@ -30,9 +30,13 @@ void ima_post_key_create_or_update(struct key *keyring, struct key *key, const void *payload, size_t payload_len, unsigned long flags, bool create) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = get_current_ns(); bool queued = false; + /* only handle key if related to init_ima_ns */ + if (ns != &init_ima_ns) + return; + /* Only asymmetric keys are handled by this hook. */ if (key->type != &key_type_asymmetric) return; diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 79a786db79db..f6fd3abcaebf 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -49,7 +49,10 @@ static ssize_t ima_show_htable_violations(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(filp); + + if (!ns_is_active(ns)) + return -EACCES; return ima_show_htable_value(buf, count, ppos, &ns->ima_htable.violations); @@ -64,7 +67,10 @@ static ssize_t ima_show_measurements_count(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(filp); + + if (!ns_is_active(ns)) + return -EACCES; return ima_show_htable_value(buf, count, ppos, &ns->ima_htable.len); } @@ -77,7 +83,7 @@ static const struct file_operations ima_measurements_count_ops = { /* returns pointer to hlist_node */ static void *ima_measurements_start(struct seq_file *m, loff_t *pos) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(m->file); loff_t l = *pos; struct ima_queue_entry *qe; @@ -95,7 +101,7 @@ static void *ima_measurements_start(struct seq_file *m, loff_t *pos) static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(m->file); struct ima_queue_entry *qe = v; /* lock protects when reading beyond last element @@ -198,6 +204,11 @@ static const struct seq_operations ima_measurments_seqops = { static int ima_measurements_open(struct inode *inode, struct file *file) { + struct ima_namespace *ns = ima_ns_from_file(file); + + if (!ns_is_active(ns)) + return -EACCES; + return seq_open(file, &ima_measurments_seqops); } @@ -264,6 +275,11 @@ static const struct seq_operations ima_ascii_measurements_seqops = { static int ima_ascii_measurements_open(struct inode *inode, struct file *file) { + struct ima_namespace *ns = ima_ns_from_file(file); + + if (!ns_is_active(ns)) + return -EACCES; + return seq_open(file, &ima_ascii_measurements_seqops); } @@ -317,10 +333,13 @@ static ssize_t ima_read_policy(struct ima_namespace *ns, char *path) static ssize_t ima_write_policy(struct file *file, const char __user *buf, size_t datalen, loff_t *ppos) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(file); char *data; ssize_t result; + if (!ns_is_active(ns)) + return -EACCES; + if (datalen >= PAGE_SIZE) datalen = PAGE_SIZE - 1; @@ -381,7 +400,10 @@ static int ima_open_policy(struct inode *inode, struct file *filp) #ifdef CONFIG_IMA_READ_POLICY struct user_namespace *user_ns = ima_user_ns_from_file(filp); #endif - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(filp); + + if (!ns_is_active(ns)) + return -EACCES; if (!(filp->f_flags & O_WRONLY)) { #ifndef CONFIG_IMA_READ_POLICY @@ -408,7 +430,7 @@ static int ima_open_policy(struct inode *inode, struct file *filp) */ static int ima_release_policy(struct inode *inode, struct file *file) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(file); const char *cause = ns->valid_policy ? "completed" : "failed"; if ((file->f_flags & O_ACCMODE) == O_RDONLY) @@ -419,7 +441,8 @@ static int ima_release_policy(struct inode *inode, struct file *file) ns->valid_policy = 0; } - pr_info("policy update %s\n", cause); + if (ns == &init_ima_ns) + pr_info("policy update %s\n", cause); integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL, "policy_update", cause, !ns->valid_policy, 0); @@ -455,7 +478,7 @@ static ssize_t ima_show_active(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(filp); char tmpbuf[2]; ssize_t len; @@ -468,7 +491,7 @@ static ssize_t ima_write_active(struct file *filp, const char __user *buf, size_t count, loff_t *ppos) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(filp); unsigned int active; char tmpbuf[3]; ssize_t ret; @@ -482,8 +505,11 @@ static ssize_t ima_write_active(struct file *filp, return ret; tmpbuf[ret] = 0; - if (!kstrtouint(tmpbuf, 10, &active) && active == 1) - atomic_set(&ns->active, 1); + if (!kstrtouint(tmpbuf, 10, &active) && active == 1) { + ret = ima_init_namespace(ns); + if (ret < 0) + count = -EINVAL; + } return count; } @@ -518,11 +544,26 @@ int ima_fs_ns_init(struct user_namespace *user_ns, struct dentry *root) struct dentry *runtime_measurements_count = NULL; struct dentry *violations = NULL; + /* + * While multiple superblocks can exist they are keyed by userns in + * s_fs_info for securityfs. The first time a userns mounts a + * securityfs instance we lazily allocate the ima_namespace for the + * userns since that's the only way a userns can meaningfully use ima. + * The vfs ensures we're the only one to call fill_super() and hence + * ima_fs_ns_init(), so we don't need any memory barriers here, i.e. + * user_ns->ima_ns can't change while we're in here. + */ + if (!ns) { + ns = create_ima_ns(); + if (IS_ERR(ns)) + return PTR_ERR(ns); + } + /* FIXME: update when evm and integrity are namespaced */ if (user_ns != &init_user_ns) { int_dir = securityfs_create_dir("integrity", root); if (IS_ERR(int_dir)) - return PTR_ERR(int_dir); + goto free_ns; } else { int_dir = integrity_dir; } @@ -575,6 +616,9 @@ int ima_fs_ns_init(struct user_namespace *user_ns, struct dentry *root) if (ns != &init_ima_ns && ima_fs_add_ns_files(ima_dir)) goto out; + if (!ima_ns_from_user_ns(user_ns)) + user_ns_set_ima_ns(user_ns, ns); + return 0; out: securityfs_remove(ns->ima_policy); @@ -587,6 +631,10 @@ int ima_fs_ns_init(struct user_namespace *user_ns, struct dentry *root) if (user_ns != &init_user_ns) securityfs_remove(int_dir); +free_ns: + if (!ima_ns_from_user_ns(user_ns)) + ima_free_ima_ns(ns); + return -1; } diff --git a/security/integrity/ima/ima_init_ima_ns.c b/security/integrity/ima/ima_init_ima_ns.c index 39ee0c2477a6..0ff587b874bd 100644 --- a/security/integrity/ima/ima_init_ima_ns.c +++ b/security/integrity/ima/ima_init_ima_ns.c @@ -46,6 +46,8 @@ int ima_init_namespace(struct ima_namespace *ns) return rc; } + atomic_set(&ns->active, 1); + return 0; } diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 059917182960..1ffac9c04df1 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -506,7 +506,7 @@ int ima_file_mmap(struct file *file, unsigned long prot) */ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = get_current_ns(); struct ima_template_desc *template = NULL; struct file *file = vma->vm_file; char filename[NAME_MAX]; @@ -519,7 +519,8 @@ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot) int pcr; /* Is mprotect making an mmap'ed file executable? */ - if (!(ns->ima_policy_flag & IMA_APPRAISE) || !vma->vm_file || + if (!ns_is_active(ns) || + !(ns->ima_policy_flag & IMA_APPRAISE) || !vma->vm_file || !(prot & PROT_EXEC) || (vma->vm_flags & VM_EXEC)) return 0; @@ -655,9 +656,9 @@ static int __ima_inode_hash(struct ima_namespace *ns, */ int ima_file_hash(struct file *file, char *buf, size_t buf_size) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = get_current_ns(); - if (!file) + if (!ns_is_active(ns) || !file) return -EINVAL; return __ima_inode_hash(ns, file_inode(file), buf, buf_size); @@ -684,9 +685,9 @@ EXPORT_SYMBOL_GPL(ima_file_hash); */ int ima_inode_hash(struct inode *inode, char *buf, size_t buf_size) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = get_current_ns(); - if (!inode) + if (!ns_is_active(ns) || !inode) return -EINVAL; return __ima_inode_hash(ns, inode, buf, buf_size); @@ -705,11 +706,11 @@ EXPORT_SYMBOL_GPL(ima_inode_hash); void ima_post_create_tmpfile(struct user_namespace *mnt_userns, struct inode *inode) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = get_current_ns(); struct integrity_iint_cache *iint; int must_appraise; - if (!ns->ima_policy_flag || !S_ISREG(inode->i_mode)) + if (!ns_is_active(ns) || !ns->ima_policy_flag || !S_ISREG(inode->i_mode)) return; must_appraise = ima_must_appraise(ns, mnt_userns, inode, MAY_ACCESS, @@ -738,12 +739,12 @@ void ima_post_create_tmpfile(struct user_namespace *mnt_userns, void ima_post_path_mknod(struct user_namespace *mnt_userns, struct dentry *dentry) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = get_current_ns(); struct integrity_iint_cache *iint; struct inode *inode = dentry->d_inode; int must_appraise; - if (!ns->ima_policy_flag || !S_ISREG(inode->i_mode)) + if (!ns_is_active(ns) || !ns->ima_policy_flag || !S_ISREG(inode->i_mode)) return; must_appraise = ima_must_appraise(ns, mnt_userns, inode, MAY_ACCESS, @@ -827,6 +828,7 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, enum kernel_read_file_id read_id) { struct user_namespace *user_ns = current_user_ns(); + struct ima_namespace *ns = ima_ns_from_user_ns(user_ns); enum ima_hooks func; u32 secid; @@ -861,8 +863,12 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, */ int ima_load_data(enum kernel_load_data_id id, bool contents) { + struct ima_namespace *ns = get_current_ns(); bool ima_enforce, sig_enforce; + if (ns != &init_ima_ns) + return 0; + ima_enforce = (ima_appraise & IMA_APPRAISE_ENFORCE) == IMA_APPRAISE_ENFORCE; @@ -1070,10 +1076,10 @@ int process_buffer_measurement(struct ima_namespace *ns, */ void ima_kexec_cmdline(int kernel_fd, const void *buf, int size) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = get_current_ns(); struct fd f; - if (!buf || !size) + if (!ns_is_active(ns) || !buf || !size) return; f = fdget(kernel_fd); @@ -1111,7 +1117,10 @@ int ima_measure_critical_data(const char *event_label, const void *buf, size_t buf_len, bool hash, u8 *digest, size_t digest_len) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = get_current_ns(); + + if (!ns_is_active(ns)) + return -EINVAL; if (!event_name || !event_label || !buf || !buf_len) return -ENOPARAM; diff --git a/security/integrity/ima/ima_ns.c b/security/integrity/ima/ima_ns.c index 29af6fea2d74..244dc9d66fb1 100644 --- a/security/integrity/ima/ima_ns.c +++ b/security/integrity/ima/ima_ns.c @@ -26,22 +26,29 @@ struct ima_namespace *create_ima_ns(void) /* destroy_ima_ns() must only be called after ima_init_namespace() was called */ static void destroy_ima_ns(struct ima_namespace *ns) { + atomic_set(&ns->active, 0); unregister_blocking_lsm_notifier(&ns->ima_lsm_policy_notifier); kfree(ns->arch_policy_entry); ima_free_policy_rules(ns); ima_free_ns_status_tree(ns); } -void free_ima_ns(struct user_namespace *user_ns) +void ima_free_ima_ns(struct ima_namespace *ns) { - struct ima_namespace *ns = user_ns->ima_ns; - if (!ns || WARN_ON(ns == &init_ima_ns)) return; - destroy_ima_ns(ns); + if (ns_is_active(ns)) + destroy_ima_ns(ns); kmem_cache_free(imans_cachep, ns); +} + +void free_ima_ns(struct user_namespace *user_ns) +{ + struct ima_namespace *ns = ima_ns_from_user_ns(user_ns); + + ima_free_ima_ns(ns); user_ns->ima_ns = NULL; } diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 151f418036ee..2b8210f0be44 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -471,7 +471,8 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, return NOTIFY_DONE; ns = container_of(nb, struct ima_namespace, ima_lsm_policy_notifier); - ima_lsm_update_rules(ns); + if (ns_is_active(ns)) + ima_lsm_update_rules(ns); return NOTIFY_OK; } @@ -1334,6 +1335,7 @@ static unsigned int ima_parse_appraise_algos(char *arg) static int ima_parse_rule(struct ima_namespace *ns, char *rule, struct ima_rule_entry *entry) { + struct user_namespace *user_ns = ima_ns_to_user_ns(ns); struct audit_buffer *ab; char *from; char *p; @@ -1583,7 +1585,7 @@ static int ima_parse_rule(struct ima_namespace *ns, result = kstrtoul(args[0].from, 10, &lnum); if (!result) { - entry->uid = make_kuid(current_user_ns(), + entry->uid = make_kuid(user_ns, (uid_t) lnum); if (!uid_valid(entry->uid) || (uid_t)lnum != lnum) @@ -1618,7 +1620,7 @@ static int ima_parse_rule(struct ima_namespace *ns, result = kstrtoul(args[0].from, 10, &lnum); if (!result) { - entry->gid = make_kgid(current_user_ns(), + entry->gid = make_kgid(user_ns, (gid_t)lnum); if (!gid_valid(entry->gid) || (((gid_t)lnum) != lnum)) @@ -1645,7 +1647,7 @@ static int ima_parse_rule(struct ima_namespace *ns, result = kstrtoul(args[0].from, 10, &lnum); if (!result) { - entry->fowner = make_kuid(current_user_ns(), + entry->fowner = make_kuid(user_ns, (uid_t)lnum); if (!uid_valid(entry->fowner) || (((uid_t)lnum) != lnum)) @@ -1671,7 +1673,7 @@ static int ima_parse_rule(struct ima_namespace *ns, result = kstrtoul(args[0].from, 10, &lnum); if (!result) { - entry->fgroup = make_kgid(current_user_ns(), + entry->fgroup = make_kgid(user_ns, (gid_t)lnum); if (!gid_valid(entry->fgroup) || (((gid_t)lnum) != lnum)) @@ -1925,7 +1927,7 @@ static const char *const mask_tokens[] = { void *ima_policy_start(struct seq_file *m, loff_t *pos) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(m->file); loff_t l = *pos; struct ima_rule_entry *entry; struct list_head *ima_rules_tmp; @@ -1944,7 +1946,7 @@ void *ima_policy_start(struct seq_file *m, loff_t *pos) void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos) { - struct ima_namespace *ns = &init_ima_ns; + struct ima_namespace *ns = ima_ns_from_file(m->file); struct ima_rule_entry *entry = v; rcu_read_lock();