Merge branch 'next-smack' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull smack updates from James Morris:
 "Two minor fixes"

* 'next-smack' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  Smack: Privilege check on key operations
  Smack: fix dereferenced before check

3 files changed, 39 insertions, 12 deletions

diff --git a/security/smack/smack.h b/security/smack/smack.h
index 6a71fc7..f7db791 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -321,6 +321,7 @@ struct smack_known *smk_import_entry(const char *, int);
 void smk_insert_entry(struct smack_known *skp);
 struct smack_known *smk_find_entry(const char *);
 bool smack_privileged(int cap);
+bool smack_privileged_cred(int cap, const struct cred *cred);
 void smk_destroy_label_list(struct list_head *list);
 
 /*
diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
index 1a30041..9a4c0ad 100644
--- a/security/smack/smack_access.c
+++ b/security/smack/smack_access.c
@@ -623,26 +623,24 @@ struct smack_known *smack_from_secid(const u32 secid)
 LIST_HEAD(smack_onlycap_list);
 DEFINE_MUTEX(smack_onlycap_lock);
 
-/*
+/**
+ * smack_privileged_cred - are all privilege requirements met by cred
+ * @cap: The requested capability
+ * @cred: the credential to use
+ *
  * Is the task privileged and allowed to be privileged
  * by the onlycap rule.
  *
  * Returns true if the task is allowed to be privileged, false if it's not.
  */
-bool smack_privileged(int cap)
+bool smack_privileged_cred(int cap, const struct cred *cred)
 {
-	struct smack_known *skp = smk_of_current();
+	struct task_smack *tsp = cred->security;
+	struct smack_known *skp = tsp->smk_task;
 	struct smack_known_list_elem *sklep;
 	int rc;
 
-	/*
-	 * All kernel tasks are privileged
-	 */
-	if (unlikely(current->flags & PF_KTHREAD))
-		return true;
-
-	rc = cap_capable(current_cred(), &init_user_ns, cap,
-				SECURITY_CAP_AUDIT);
+	rc = cap_capable(cred, &init_user_ns, cap, SECURITY_CAP_AUDIT);
 	if (rc)
 		return false;
 
@@ -662,3 +660,23 @@ bool smack_privileged(int cap)
 
 	return false;
 }
+
+/**
+ * smack_privileged - are all privilege requirements met
+ * @cap: The requested capability
+ *
+ * Is the task privileged and allowed to be privileged
+ * by the onlycap rule.
+ *
+ * Returns true if the task is allowed to be privileged, false if it's not.
+ */
+bool smack_privileged(int cap)
+{
+	/*
+	 * All kernel tasks are privileged
+	 */
+	if (unlikely(current->flags & PF_KTHREAD))
+		return true;
+
+	return smack_privileged_cred(cap, current_cred());
+}
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 14cc794..03fdecb 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -2866,12 +2866,16 @@ static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
 #endif
 #ifdef SMACK_IPV6_SECMARK_LABELING
 	struct smack_known *rsp;
-	struct socket_smack *ssp = sock->sk->sk_security;
+	struct socket_smack *ssp;
 #endif
 
 	if (sock->sk == NULL)
 		return 0;
 
+#ifdef SMACK_IPV6_SECMARK_LABELING
+	ssp = sock->sk->sk_security;
+#endif
+
 	switch (sock->sk->sk_family) {
 	case PF_INET:
 		if (addrlen < sizeof(struct sockaddr_in))
@@ -4365,6 +4369,10 @@ static int smack_key_permission(key_ref_t key_ref,
 	 */
 	if (tkp == NULL)
 		return -EACCES;
+
+	if (smack_privileged_cred(CAP_MAC_OVERRIDE, cred))
+		return 0;
+
 #ifdef CONFIG_AUDIT
 	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
 	ad.a.u.key_struct.key = keyp->serial;