18 files changed, 260 insertions, 61 deletions

diff --git a/security/selinux/Makefile b/security/selinux/Makefile
index 4d8e0e8adf0b..776162444882 100644
--- a/security/selinux/Makefile
+++ b/security/selinux/Makefile
@@ -16,6 +16,8 @@ selinux-$(CONFIG_NETLABEL) += netlabel.o
 
 selinux-$(CONFIG_SECURITY_INFINIBAND) += ibpkey.o
 
+selinux-$(CONFIG_IMA) += ima.o
+
 ccflags-y := -I$(srctree)/security/selinux -I$(srctree)/security/selinux/include
 
 $(addprefix $(obj)/,$(selinux-y)): $(obj)/flask.h
diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 3c05827608b6..ad451cf9375e 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -118,11 +118,11 @@ void avc_set_cache_threshold(struct selinux_avc *avc,
 	avc->avc_cache_threshold = cache_threshold;
 }
 
-static struct avc_callback_node *avc_callbacks;
-static struct kmem_cache *avc_node_cachep;
-static struct kmem_cache *avc_xperms_data_cachep;
-static struct kmem_cache *avc_xperms_decision_cachep;
-static struct kmem_cache *avc_xperms_cachep;
+static struct avc_callback_node *avc_callbacks __ro_after_init;
+static struct kmem_cache *avc_node_cachep __ro_after_init;
+static struct kmem_cache *avc_xperms_data_cachep __ro_after_init;
+static struct kmem_cache *avc_xperms_decision_cachep __ro_after_init;
+static struct kmem_cache *avc_xperms_cachep __ro_after_init;
 
 static inline int avc_hash(u32 ssid, u32 tsid, u16 tclass)
 {
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 644b17ec9e63..af2994adf9dd 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -484,6 +484,55 @@ static int selinux_is_sblabel_mnt(struct super_block *sb)
 	}
 }
 
+static int sb_check_xattr_support(struct super_block *sb)
+{
+	struct superblock_security_struct *sbsec = sb->s_security;
+	struct dentry *root = sb->s_root;
+	struct inode *root_inode = d_backing_inode(root);
+	u32 sid;
+	int rc;
+
+	/*
+	 * Make sure that the xattr handler exists and that no
+	 * error other than -ENODATA is returned by getxattr on
+	 * the root directory.  -ENODATA is ok, as this may be
+	 * the first boot of the SELinux kernel before we have
+	 * assigned xattr values to the filesystem.
+	 */
+	if (!(root_inode->i_opflags & IOP_XATTR)) {
+		pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
+			sb->s_id, sb->s_type->name);
+		goto fallback;
+	}
+
+	rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
+	if (rc < 0 && rc != -ENODATA) {
+		if (rc == -EOPNOTSUPP) {
+			pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
+				sb->s_id, sb->s_type->name);
+			goto fallback;
+		} else {
+			pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
+				sb->s_id, sb->s_type->name, -rc);
+			return rc;
+		}
+	}
+	return 0;
+
+fallback:
+	/* No xattr support - try to fallback to genfs if possible. */
+	rc = security_genfs_sid(&selinux_state, sb->s_type->name, "/",
+				SECCLASS_DIR, &sid);
+	if (rc)
+		return -EOPNOTSUPP;
+
+	pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
+		sb->s_id, sb->s_type->name);
+	sbsec->behavior = SECURITY_FS_USE_GENFS;
+	sbsec->sid = sid;
+	return 0;
+}
+
 static int sb_finish_set_opts(struct super_block *sb)
 {
 	struct superblock_security_struct *sbsec = sb->s_security;
@@ -492,30 +541,9 @@ static int sb_finish_set_opts(struct super_block *sb)
 	int rc = 0;
 
 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
-		/* Make sure that the xattr handler exists and that no
-		   error other than -ENODATA is returned by getxattr on
-		   the root directory.  -ENODATA is ok, as this may be
-		   the first boot of the SELinux kernel before we have
-		   assigned xattr values to the filesystem. */
-		if (!(root_inode->i_opflags & IOP_XATTR)) {
-			pr_warn("SELinux: (dev %s, type %s) has no "
-			       "xattr support\n", sb->s_id, sb->s_type->name);
-			rc = -EOPNOTSUPP;
-			goto out;
-		}
-
-		rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
-		if (rc < 0 && rc != -ENODATA) {
-			if (rc == -EOPNOTSUPP)
-				pr_warn("SELinux: (dev %s, type "
-				       "%s) has no security xattr handler\n",
-				       sb->s_id, sb->s_type->name);
-			else
-				pr_warn("SELinux: (dev %s, type "
-				       "%s) getxattr errno %d\n", sb->s_id,
-				       sb->s_type->name, -rc);
-			goto out;
-		}
+		rc = sb_check_xattr_support(sb);
+		if (rc)
+			return rc;
 	}
 
 	sbsec->flags |= SE_SBINITIALIZED;
@@ -554,7 +582,6 @@ static int sb_finish_set_opts(struct super_block *sb)
 		spin_lock(&sbsec->isec_lock);
 	}
 	spin_unlock(&sbsec->isec_lock);
-out:
 	return rc;
 }
 
@@ -1120,7 +1147,8 @@ static inline u16 inode_mode_to_security_class(umode_t mode)
 
 static inline int default_protocol_stream(int protocol)
 {
-	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
+	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
+		protocol == IPPROTO_MPTCP);
 }
 
 static inline int default_protocol_dgram(int protocol)
@@ -2934,6 +2962,62 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
 	return 0;
 }
 
+static int selinux_inode_init_security_anon(struct inode *inode,
+					    const struct qstr *name,
+					    const struct inode *context_inode)
+{
+	const struct task_security_struct *tsec = selinux_cred(current_cred());
+	struct common_audit_data ad;
+	struct inode_security_struct *isec;
+	int rc;
+
+	if (unlikely(!selinux_initialized(&selinux_state)))
+		return 0;
+
+	isec = selinux_inode(inode);
+
+	/*
+	 * We only get here once per ephemeral inode.  The inode has
+	 * been initialized via inode_alloc_security but is otherwise
+	 * untouched.
+	 */
+
+	if (context_inode) {
+		struct inode_security_struct *context_isec =
+			selinux_inode(context_inode);
+		if (context_isec->initialized != LABEL_INITIALIZED) {
+			pr_err("SELinux:  context_inode is not initialized");
+			return -EACCES;
+		}
+
+		isec->sclass = context_isec->sclass;
+		isec->sid = context_isec->sid;
+	} else {
+		isec->sclass = SECCLASS_ANON_INODE;
+		rc = security_transition_sid(
+			&selinux_state, tsec->sid, tsec->sid,
+			isec->sclass, name, &isec->sid);
+		if (rc)
+			return rc;
+	}
+
+	isec->initialized = LABEL_INITIALIZED;
+	/*
+	 * Now that we've initialized security, check whether we're
+	 * allowed to actually create this type of anonymous inode.
+	 */
+
+	ad.type = LSM_AUDIT_DATA_INODE;
+	ad.u.inode = inode;
+
+	return avc_has_perm(&selinux_state,
+			    tsec->sid,
+			    isec->sid,
+			    isec->sclass,
+			    FILE__CREATE,
+			    &ad);
+}
+
 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
 {
 	return may_create(dir, dentry, SECCLASS_FILE);
@@ -3413,6 +3497,10 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name,
 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
 {
 	const int len = sizeof(XATTR_NAME_SELINUX);
+
+	if (!selinux_initialized(&selinux_state))
+		return 0;
+
 	if (buffer && len <= buffer_size)
 		memcpy(buffer, XATTR_NAME_SELINUX, len);
 	return len;
@@ -7000,6 +7088,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
 
 	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
 	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
+	LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
 	LSM_HOOK_INIT(inode_create, selinux_inode_create),
 	LSM_HOOK_INIT(inode_link, selinux_inode_link),
 	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
diff --git a/security/selinux/ibpkey.c b/security/selinux/ibpkey.c
index 3a63a989e55e..20b3b2243820 100644
--- a/security/selinux/ibpkey.c
+++ b/security/selinux/ibpkey.c
@@ -40,7 +40,6 @@ struct sel_ib_pkey {
 	struct rcu_head rcu;
 };
 
-static LIST_HEAD(sel_ib_pkey_list);
 static DEFINE_SPINLOCK(sel_ib_pkey_lock);
 static struct sel_ib_pkey_bkt sel_ib_pkey_hash[SEL_PKEY_HASH_SIZE];
 
diff --git a/security/selinux/ima.c b/security/selinux/ima.c
new file mode 100644
index 000000000000..03715893ff97
--- /dev/null
+++ b/security/selinux/ima.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2021 Microsoft Corporation
+ *
+ * Author: Lakshmi Ramasubramanian (nramas@linux.microsoft.com)
+ *
+ * Measure critical data structures maintainted by SELinux
+ * using IMA subsystem.
+ */
+#include <linux/vmalloc.h>
+#include <linux/ima.h>
+#include "security.h"
+#include "ima.h"
+
+/*
+ * selinux_ima_measure_state - Measure hash of the SELinux policy
+ *
+ * @state: selinux state struct
+ *
+ * NOTE: This function must be called with policy_mutex held.
+ */
+void selinux_ima_measure_state(struct selinux_state *state)
+{
+	void *policy = NULL;
+	size_t policy_len;
+	int rc = 0;
+
+	/*
+	 * Measure SELinux policy only after initialization is completed.
+	 */
+	if (!selinux_initialized(state))
+		return;
+
+	rc = security_read_state_kernel(state, &policy, &policy_len);
+	if (rc) {
+		pr_err("SELinux: %s: failed to read policy %d.\n", __func__, rc);
+		return;
+	}
+
+	ima_measure_critical_data("selinux", "selinux-policy-hash",
+				  policy, policy_len, true);
+
+	vfree(policy);
+}
diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h
index 40cebde62856..ba2e01a6955c 100644
--- a/security/selinux/include/classmap.h
+++ b/security/selinux/include/classmap.h
@@ -249,6 +249,8 @@ struct security_class_mapping secclass_map[] = {
 	  {"open", "cpu", "kernel", "tracepoint", "read", "write"} },
 	{ "lockdown",
 	  { "integrity", "confidentiality", NULL } },
+	{ "anon_inode",
+	  { COMMON_FILE_PERMS, NULL } },
 	{ NULL }
   };
 
diff --git a/security/selinux/include/ima.h b/security/selinux/include/ima.h
new file mode 100644
index 000000000000..d69c36611423
--- /dev/null
+++ b/security/selinux/include/ima.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2021 Microsoft Corporation
+ *
+ * Author: Lakshmi Ramasubramanian (nramas@linux.microsoft.com)
+ *
+ * Measure critical data structures maintainted by SELinux
+ * using IMA subsystem.
+ */
+
+#ifndef _SELINUX_IMA_H_
+#define _SELINUX_IMA_H_
+
+#include "security.h"
+
+#ifdef CONFIG_IMA
+extern void selinux_ima_measure_state(struct selinux_state *selinux_state);
+#else
+static inline void selinux_ima_measure_state(struct selinux_state *selinux_state)
+{
+}
+#endif
+
+#endif	/* _SELINUX_IMA_H_ */
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index 3cc8bab31ea8..6fe25300b89d 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -229,7 +229,8 @@ void selinux_policy_cancel(struct selinux_state *state,
 			struct selinux_policy *policy);
 int security_read_policy(struct selinux_state *state,
 			 void **data, size_t *len);
-
+int security_read_state_kernel(struct selinux_state *state,
+			       void **data, size_t *len);
 int security_policycap_supported(struct selinux_state *state,
 				 unsigned int req_cap);
 
@@ -436,7 +437,6 @@ extern void selinux_complete_init(void);
 extern int selinux_disable(struct selinux_state *state);
 extern void exit_sel_fs(void);
 extern struct path selinux_null;
-extern struct vfsmount *selinuxfs_mount;
 extern void selnl_notify_setenforce(int val);
 extern void selnl_notify_policyload(u32 seqno);
 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
diff --git a/security/selinux/netif.c b/security/selinux/netif.c
index 86813b46fad5..1ab03efe7494 100644
--- a/security/selinux/netif.c
+++ b/security/selinux/netif.c
@@ -36,7 +36,6 @@ struct sel_netif {
 };
 
 static u32 sel_netif_total;
-static LIST_HEAD(sel_netif_list);
 static DEFINE_SPINLOCK(sel_netif_lock);
 static struct list_head sel_netif_hash[SEL_NETIF_HASH_SIZE];
 
diff --git a/security/selinux/netlink.c b/security/selinux/netlink.c
index 621e2e9cd6a1..1760aee712fd 100644
--- a/security/selinux/netlink.c
+++ b/security/selinux/netlink.c
@@ -19,7 +19,7 @@
 
 #include "security.h"
 
-static struct sock *selnl;
+static struct sock *selnl __ro_after_init;
 
 static int selnl_msglen(int msgtype)
 {
diff --git a/security/selinux/netnode.c b/security/selinux/netnode.c
index 461fb548453a..4a7d2ab5b960 100644
--- a/security/selinux/netnode.c
+++ b/security/selinux/netnode.c
@@ -54,7 +54,6 @@ struct sel_netnode {
  * if this becomes a problem we can always add a hash table for each address
  * family later */
 
-static LIST_HEAD(sel_netnode_list);
 static DEFINE_SPINLOCK(sel_netnode_lock);
 static struct sel_netnode_bkt sel_netnode_hash[SEL_NETNODE_HASH_SIZE];
 
diff --git a/security/selinux/netport.c b/security/selinux/netport.c
index d340f4dcdf5f..b8bc3897891d 100644
--- a/security/selinux/netport.c
+++ b/security/selinux/netport.c
@@ -53,7 +53,6 @@ struct sel_netport {
  * if this becomes a problem we can always add a hash table for each address
  * family later */
 
-static LIST_HEAD(sel_netport_list);
 static DEFINE_SPINLOCK(sel_netport_lock);
 static struct sel_netport_bkt sel_netport_hash[SEL_NETPORT_HASH_SIZE];
 
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index 4bde570d56a2..01a7d50ed39b 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -2204,8 +2204,8 @@ static struct file_system_type sel_fs_type = {
 	.kill_sb	= sel_kill_sb,
 };
 
-struct vfsmount *selinuxfs_mount;
-struct path selinux_null;
+static struct vfsmount *selinuxfs_mount __ro_after_init;
+struct path selinux_null __ro_after_init;
 
 static int __init init_sel_fs(void)
 {
diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c
index 0172d87e2b9a..6dcb6aa4db7f 100644
--- a/security/selinux/ss/avtab.c
+++ b/security/selinux/ss/avtab.c
@@ -23,8 +23,8 @@
 #include "avtab.h"
 #include "policydb.h"
 
-static struct kmem_cache *avtab_node_cachep;
-static struct kmem_cache *avtab_xperms_cachep;
+static struct kmem_cache *avtab_node_cachep __ro_after_init;
+static struct kmem_cache *avtab_xperms_cachep __ro_after_init;
 
 /* Based on MurmurHash3, written by Austin Appleby and placed in the
  * public domain.
diff --git a/security/selinux/ss/ebitmap.c b/security/selinux/ss/ebitmap.c
index 14bedc95c6dc..61fcbb8d0f88 100644
--- a/security/selinux/ss/ebitmap.c
+++ b/security/selinux/ss/ebitmap.c
@@ -26,7 +26,7 @@
 
 #define BITS_PER_U64	(sizeof(u64) * 8)
 
-static struct kmem_cache *ebitmap_node_cachep;
+static struct kmem_cache *ebitmap_node_cachep __ro_after_init;
 
 int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2)
 {
diff --git a/security/selinux/ss/hashtab.c b/security/selinux/ss/hashtab.c
index dab8c25c739b..3881787ce492 100644
--- a/security/selinux/ss/hashtab.c
+++ b/security/selinux/ss/hashtab.c
@@ -9,7 +9,7 @@
 #include <linux/errno.h>
 #include "hashtab.h"
 
-static struct kmem_cache *hashtab_node_cachep;
+static struct kmem_cache *hashtab_node_cachep __ro_after_init;
 
 /*
  * Here we simply round the number of elements up to the nearest power of two.
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index 597b79703584..3438d0130378 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -65,6 +65,7 @@
 #include "ebitmap.h"
 #include "audit.h"
 #include "policycap_names.h"
+#include "ima.h"
 
 /* Forward declaration. */
 static int context_struct_to_string(struct policydb *policydb,
@@ -2178,6 +2179,7 @@ static void selinux_notify_policy_change(struct selinux_state *state,
 	selinux_status_update_policyload(state, seqno);
 	selinux_netlbl_cache_invalidate();
 	selinux_xfrm_notify_policyload();
+	selinux_ima_measure_state(state);
 }
 
 void selinux_policy_commit(struct selinux_state *state,
@@ -3693,15 +3695,11 @@ out:
 	return match;
 }
 
-static int (*aurule_callback)(void) = audit_update_lsm_rules;
-
 static int aurule_avc_callback(u32 event)
 {
-	int err = 0;
-
-	if (event == AVC_CALLBACK_RESET && aurule_callback)
-		err = aurule_callback();
-	return err;
+	if (event == AVC_CALLBACK_RESET)
+		return audit_update_lsm_rules();
+	return 0;
 }
 
 static int __init aurule_init(void)
@@ -3874,7 +3872,32 @@ out:
 #endif /* CONFIG_NETLABEL */
 
 /**
+ * __security_read_policy - read the policy.
+ * @policy: SELinux policy
+ * @data: binary policy data
+ * @len: length of data in bytes
+ *
+ */
+static int __security_read_policy(struct selinux_policy *policy,
+				  void *data, size_t *len)
+{
+	int rc;
+	struct policy_file fp;
+
+	fp.data = data;
+	fp.len = *len;
+
+	rc = policydb_write(&policy->policydb, &fp);
+	if (rc)
+		return rc;
+
+	*len = (unsigned long)fp.data - (unsigned long)data;
+	return 0;
+}
+
+/**
  * security_read_policy - read the policy.
+ * @state: selinux_state
  * @data: binary policy data
  * @len: length of data in bytes
  *
@@ -3883,8 +3906,6 @@ int security_read_policy(struct selinux_state *state,
 			 void **data, size_t *len)
 {
 	struct selinux_policy *policy;
-	int rc;
-	struct policy_file fp;
 
 	policy = rcu_dereference_protected(
 			state->policy, lockdep_is_held(&state->policy_mutex));
@@ -3896,14 +3917,35 @@ int security_read_policy(struct selinux_state *state,
 	if (!*data)
 		return -ENOMEM;
 
-	fp.data = *data;
-	fp.len = *len;
+	return __security_read_policy(policy, *data, len);
+}
 
-	rc = policydb_write(&policy->policydb, &fp);
-	if (rc)
-		return rc;
+/**
+ * security_read_state_kernel - read the policy.
+ * @state: selinux_state
+ * @data: binary policy data
+ * @len: length of data in bytes
+ *
+ * Allocates kernel memory for reading SELinux policy.
+ * This function is for internal use only and should not
+ * be used for returning data to user space.
+ *
+ * This function must be called with policy_mutex held.
+ */
+int security_read_state_kernel(struct selinux_state *state,
+			       void **data, size_t *len)
+{
+	struct selinux_policy *policy;
 
-	*len = (unsigned long)fp.data - (unsigned long)*data;
-	return 0;
+	policy = rcu_dereference_protected(
+			state->policy, lockdep_is_held(&state->policy_mutex));
+	if (!policy)
+		return -EINVAL;
+
+	*len = policy->policydb.len;
+	*data = vmalloc(*len);
+	if (!*data)
+		return -ENOMEM;
 
+	return __security_read_policy(policy, *data, len);
 }
diff --git a/security/selinux/xfrm.c b/security/selinux/xfrm.c
index c367d36965d4..634f3db24da6 100644
--- a/security/selinux/xfrm.c
+++ b/security/selinux/xfrm.c
@@ -47,7 +47,7 @@
 #include "xfrm.h"
 
 /* Labeled XFRM instance counter */
-atomic_t selinux_xfrm_refcount = ATOMIC_INIT(0);
+atomic_t selinux_xfrm_refcount __read_mostly = ATOMIC_INIT(0);
 
 /*
  * Returns true if the context is an LSM/SELinux context.