Merge tag 'apparmor-pr-2018-11-01' of git://git.kernel.org/pub/scm/li…

…nux/kernel/git/jj/linux-apparmor

Pull apparmor updates from John Johansen:
 "Features/Improvements:
   - replace spin_is_locked() with lockdep
   - add base support for secmark labeling and matching

  Cleanups:
   - clean an indentation issue, remove extraneous space
   - remove no-op permission check in policy_unpack
   - fix checkpatch missing spaces error in Parse secmark policy
   - fix network performance issue in aa_label_sk_perm

  Bug fixes:
   - add #ifdef checks for secmark filtering
   - fix an error code in __aa_create_ns()
   - don't try to replace stale label in ptrace checks
   - fix failure to audit context info in build_change_hat
   - check buffer bounds when mapping permissions mask
   - fully initialize aa_perms struct when answering userspace query
   - fix uninitialized value in aa_split_fqname"

* tag 'apparmor-pr-2018-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
  apparmor: clean an indentation issue, remove extraneous space
  apparmor: fix checkpatch error in Parse secmark policy
  apparmor: add #ifdef checks for secmark filtering
  apparmor: Fix uninitialized value in aa_split_fqname
  apparmor: don't try to replace stale label in ptraceme check
  apparmor: Replace spin_is_locked() with lockdep
  apparmor: Allow filtering based on secmark policy
  apparmor: Parse secmark policy
  apparmor: Add a wildcard secid
  apparmor: don't try to replace stale label in ptrace access check
  apparmor: Fix network performance issue in aa_label_sk_perm

security/apparmor/apparmorfs.c

@@ -1742,7 +1742,7 @@ static int ns_rmdir_op(struct inode *dir, struct dentry *dentry)
 	if (error)
 		return error;
 
-	 parent = aa_get_ns(dir->i_private);
+	parent = aa_get_ns(dir->i_private);
 	/* rmdir calls the generic securityfs functions to remove files
 	 * from the apparmor dir. It is up to the apparmor ns locking
 	 * to avoid races.

security/apparmor/file.c

@@ -496,7 +496,7 @@ static void update_file_ctx(struct aa_file_ctx *fctx, struct aa_label *label,
 	/* update caching of label on file_ctx */
 	spin_lock(&fctx->lock);
 	old = rcu_dereference_protected(fctx->label,
-					spin_is_locked(&fctx->lock));
+					lockdep_is_held(&fctx->lock));
 	l = aa_label_merge(old, label, GFP_ATOMIC);
 	if (l) {
 		if (l != old) {

security/apparmor/include/cred.h

@@ -151,6 +151,8 @@ static inline struct aa_label *begin_current_label_crit_section(void)
 {
 	struct aa_label *label = aa_current_raw_label();
 
+	might_sleep();
+
 	if (label_is_stale(label)) {
 		label = aa_get_newest_label(label);
 		if (aa_replace_current_label(label) == 0)

security/apparmor/include/net.h

@@ -83,6 +83,13 @@ struct aa_sk_ctx {
 	__e;					\
 })
 
+struct aa_secmark {
+	u8 audit;
+	u8 deny;
+	u32 secid;
+	char *label;
+};
+
 extern struct aa_sfs_entry aa_sfs_entry_network[];
 
 void audit_net_cb(struct audit_buffer *ab, void *va);
@@ -103,4 +110,7 @@ int aa_sk_perm(const char *op, u32 request, struct sock *sk);
 int aa_sock_file_perm(struct aa_label *label, const char *op, u32 request,
 		      struct socket *sock);
 
+int apparmor_secmark_check(struct aa_label *label, char *op, u32 request,
+			   u32 secid, struct sock *sk);
+
 #endif /* __AA_NET_H */

security/apparmor/include/policy.h

@@ -155,6 +155,9 @@ struct aa_profile {
 
 	struct aa_rlimit rlimits;
 
+	int secmark_count;
+	struct aa_secmark *secmark;
+
 	struct aa_loaddata *rawdata;
 	unsigned char *hash;
 	char *dirname;

security/apparmor/include/secid.h

@@ -22,6 +22,9 @@ struct aa_label;
 /* secid value that will not be allocated */
 #define AA_SECID_INVALID 0
 
+/* secid value that matches any other secid */
+#define AA_SECID_WILDCARD 1
+
 struct aa_label *aa_secid_to_label(u32 secid);
 int apparmor_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
 int apparmor_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);

security/apparmor/lib.c

@@ -90,10 +90,12 @@ const char *aa_splitn_fqname(const char *fqname, size_t n, const char **ns_name,
 	const char *end = fqname + n;
 	const char *name = skipn_spaces(fqname, n);
 
-	if (!name)
-		return NULL;
 	*ns_name = NULL;
 	*ns_len = 0;
+
+	if (!name)
+		return NULL;
+
 	if (name[0] == ':') {
 		char *split = strnchr(&name[1], end - &name[1], ':');
 		*ns_name = skipn_spaces(&name[1], end - &name[1]);

security/apparmor/lsm.c

@@ -23,6 +23,8 @@
 #include <linux/sysctl.h>
 #include <linux/audit.h>
 #include <linux/user_namespace.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/netfilter_ipv6.h>
 #include <net/sock.h>
 
 #include "include/apparmor.h"
@@ -114,13 +116,13 @@ static int apparmor_ptrace_access_check(struct task_struct *child,
 	struct aa_label *tracer, *tracee;
 	int error;
 
-	tracer = begin_current_label_crit_section();
+	tracer = __begin_current_label_crit_section();
 	tracee = aa_get_task_label(child);
 	error = aa_may_ptrace(tracer, tracee,
 			(mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
 						  : AA_PTRACE_TRACE);
 	aa_put_label(tracee);
-	end_current_label_crit_section(tracer);
+	__end_current_label_crit_section(tracer);
 
 	return error;
 }
@@ -130,11 +132,11 @@ static int apparmor_ptrace_traceme(struct task_struct *parent)
 	struct aa_label *tracer, *tracee;
 	int error;
 
-	tracee = begin_current_label_crit_section();
+	tracee = __begin_current_label_crit_section();
 	tracer = aa_get_task_label(parent);
 	error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
 	aa_put_label(tracer);
-	end_current_label_crit_section(tracee);
+	__end_current_label_crit_section(tracee);
 
 	return error;
 }
@@ -1020,6 +1022,7 @@ static int apparmor_socket_shutdown(struct socket *sock, int how)
 	return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
 }
 
+#ifdef CONFIG_NETWORK_SECMARK
 /**
  * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
  *
@@ -1030,8 +1033,15 @@ static int apparmor_socket_shutdown(struct socket *sock, int how)
  */
 static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
-	return 0;
+	struct aa_sk_ctx *ctx = SK_CTX(sk);
+
+	if (!skb->secmark)
+		return 0;
+
+	return apparmor_secmark_check(ctx->label, OP_RECVMSG, AA_MAY_RECEIVE,
+				      skb->secmark, sk);
 }
+#endif
 
 
 static struct aa_label *sk_peer_label(struct sock *sk)
@@ -1126,6 +1136,20 @@ static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
 		ctx->label = aa_get_current_label();
 }
 
+#ifdef CONFIG_NETWORK_SECMARK
+static int apparmor_inet_conn_request(struct sock *sk, struct sk_buff *skb,
+				      struct request_sock *req)
+{
+	struct aa_sk_ctx *ctx = SK_CTX(sk);
+
+	if (!skb->secmark)
+		return 0;
+
+	return apparmor_secmark_check(ctx->label, OP_CONNECT, AA_MAY_CONNECT,
+				      skb->secmark, sk);
+}
+#endif
+
 static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
 	LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
@@ -1177,12 +1201,17 @@ static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
 	LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
 	LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
+#ifdef CONFIG_NETWORK_SECMARK
 	LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
+#endif
 	LSM_HOOK_INIT(socket_getpeersec_stream,
 		      apparmor_socket_getpeersec_stream),
 	LSM_HOOK_INIT(socket_getpeersec_dgram,
 		      apparmor_socket_getpeersec_dgram),
 	LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
+#ifdef CONFIG_NETWORK_SECMARK
+	LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
+#endif
 
 	LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
 	LSM_HOOK_INIT(cred_free, apparmor_cred_free),
@@ -1538,6 +1567,97 @@ static inline int apparmor_init_sysctl(void)
 }
 #endif /* CONFIG_SYSCTL */
 
+#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
+static unsigned int apparmor_ip_postroute(void *priv,
+					  struct sk_buff *skb,
+					  const struct nf_hook_state *state)
+{
+	struct aa_sk_ctx *ctx;
+	struct sock *sk;
+
+	if (!skb->secmark)
+		return NF_ACCEPT;
+
+	sk = skb_to_full_sk(skb);
+	if (sk == NULL)
+		return NF_ACCEPT;
+
+	ctx = SK_CTX(sk);
+	if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
+				    skb->secmark, sk))
+		return NF_ACCEPT;
+
+	return NF_DROP_ERR(-ECONNREFUSED);
+
+}
+
+static unsigned int apparmor_ipv4_postroute(void *priv,
+					    struct sk_buff *skb,
+					    const struct nf_hook_state *state)
+{
+	return apparmor_ip_postroute(priv, skb, state);
+}
+
+static unsigned int apparmor_ipv6_postroute(void *priv,
+					    struct sk_buff *skb,
+					    const struct nf_hook_state *state)
+{
+	return apparmor_ip_postroute(priv, skb, state);
+}
+
+static const struct nf_hook_ops apparmor_nf_ops[] = {
+	{
+		.hook =         apparmor_ipv4_postroute,
+		.pf =           NFPROTO_IPV4,
+		.hooknum =      NF_INET_POST_ROUTING,
+		.priority =     NF_IP_PRI_SELINUX_FIRST,
+	},
+#if IS_ENABLED(CONFIG_IPV6)
+	{
+		.hook =         apparmor_ipv6_postroute,
+		.pf =           NFPROTO_IPV6,
+		.hooknum =      NF_INET_POST_ROUTING,
+		.priority =     NF_IP6_PRI_SELINUX_FIRST,
+	},
+#endif
+};
+
+static int __net_init apparmor_nf_register(struct net *net)
+{
+	int ret;
+
+	ret = nf_register_net_hooks(net, apparmor_nf_ops,
+				    ARRAY_SIZE(apparmor_nf_ops));
+	return ret;
+}
+
+static void __net_exit apparmor_nf_unregister(struct net *net)
+{
+	nf_unregister_net_hooks(net, apparmor_nf_ops,
+				ARRAY_SIZE(apparmor_nf_ops));
+}
+
+static struct pernet_operations apparmor_net_ops = {
+	.init = apparmor_nf_register,
+	.exit = apparmor_nf_unregister,
+};
+
+static int __init apparmor_nf_ip_init(void)
+{
+	int err;
+
+	if (!apparmor_enabled)
+		return 0;
+
+	err = register_pernet_subsys(&apparmor_net_ops);
+	if (err)
+		panic("Apparmor: register_pernet_subsys: error %d\n", err);
+
+	return 0;
+}
+__initcall(apparmor_nf_ip_init);
+#endif
+
 static int __init apparmor_init(void)
 {
 	int error;

security/apparmor/net.c

@@ -18,6 +18,7 @@
 #include "include/label.h"
 #include "include/net.h"
 #include "include/policy.h"
+#include "include/secid.h"
 
 #include "net_names.h"
 
@@ -146,17 +147,20 @@ int aa_af_perm(struct aa_label *label, const char *op, u32 request, u16 family,
 static int aa_label_sk_perm(struct aa_label *label, const char *op, u32 request,
 			    struct sock *sk)
 {
-	struct aa_profile *profile;
-	DEFINE_AUDIT_SK(sa, op, sk);
+	int error = 0;
 
 	AA_BUG(!label);
 	AA_BUG(!sk);
 
-	if (unconfined(label))
-		return 0;
+	if (!unconfined(label)) {
+		struct aa_profile *profile;
+		DEFINE_AUDIT_SK(sa, op, sk);
 
-	return fn_for_each_confined(label, profile,
-			aa_profile_af_sk_perm(profile, &sa, request, sk));
+		error = fn_for_each_confined(label, profile,
+			    aa_profile_af_sk_perm(profile, &sa, request, sk));
+	}
+
+	return error;
 }
 
 int aa_sk_perm(const char *op, u32 request, struct sock *sk)
@@ -185,3 +189,70 @@ int aa_sock_file_perm(struct aa_label *label, const char *op, u32 request,
 
 	return aa_label_sk_perm(label, op, request, sock->sk);
 }
+
+#ifdef CONFIG_NETWORK_SECMARK
+static int apparmor_secmark_init(struct aa_secmark *secmark)
+{
+	struct aa_label *label;
+
+	if (secmark->label[0] == '*') {
+		secmark->secid = AA_SECID_WILDCARD;
+		return 0;
+	}
+
+	label = aa_label_strn_parse(&root_ns->unconfined->label,
+				    secmark->label, strlen(secmark->label),
+				    GFP_ATOMIC, false, false);
+
+	if (IS_ERR(label))
+		return PTR_ERR(label);
+
+	secmark->secid = label->secid;
+
+	return 0;
+}
+
+static int aa_secmark_perm(struct aa_profile *profile, u32 request, u32 secid,
+			   struct common_audit_data *sa, struct sock *sk)
+{
+	int i, ret;
+	struct aa_perms perms = { };
+
+	if (profile->secmark_count == 0)
+		return 0;
+
+	for (i = 0; i < profile->secmark_count; i++) {
+		if (!profile->secmark[i].secid) {
+			ret = apparmor_secmark_init(&profile->secmark[i]);
+			if (ret)
+				return ret;
+		}
+
+		if (profile->secmark[i].secid == secid ||
+		    profile->secmark[i].secid == AA_SECID_WILDCARD) {
+			if (profile->secmark[i].deny)
+				perms.deny = ALL_PERMS_MASK;
+			else
+				perms.allow = ALL_PERMS_MASK;
+
+			if (profile->secmark[i].audit)
+				perms.audit = ALL_PERMS_MASK;
+		}
+	}
+
+	aa_apply_modes_to_perms(profile, &perms);
+
+	return aa_check_perms(profile, &perms, request, sa, audit_net_cb);
+}
+
+int apparmor_secmark_check(struct aa_label *label, char *op, u32 request,
+			   u32 secid, struct sock *sk)
+{
+	struct aa_profile *profile;
+	DEFINE_AUDIT_SK(sa, op, sk);
+
+	return fn_for_each_confined(label, profile,
+				    aa_secmark_perm(profile, request, secid,
+						    &sa, sk));
+}
+#endif