1 files changed, 40 insertions, 8 deletions

diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
index b3b59b1e93d..c062e9467b6 100644
--- a/security/smack/smack_access.c
+++ b/security/smack/smack_access.c
@@ -84,6 +84,8 @@ int log_policy = SMACK_AUDIT_DENIED;
  *
  * Do the object check first because that is more
  * likely to differ.
+ *
+ * Allowing write access implies allowing locking.
  */
 int smk_access_entry(char *subject_label, char *object_label,
 			struct list_head *rule_list)
@@ -99,6 +101,11 @@ int smk_access_entry(char *subject_label, char *object_label,
 		}
 	}
 
+	/*
+	 * MAY_WRITE implies MAY_LOCK.
+	 */
+	if ((may & MAY_WRITE) == MAY_WRITE)
+		may |= MAY_LOCK;
 	return may;
 }
 
@@ -185,20 +192,21 @@ out_audit:
 }
 
 /**
- * smk_curacc - determine if current has a specific access to an object
+ * smk_tskacc - determine if a task has a specific access to an object
+ * @tsp: a pointer to the subject task
  * @obj_label: a pointer to the object's Smack label
  * @mode: the access requested, in "MAY" format
  * @a : common audit data
  *
- * This function checks the current subject label/object label pair
+ * This function checks the subject task's label/object label pair
  * in the access rule list and returns 0 if the access is permitted,
- * non zero otherwise. It allows that current may have the capability
+ * non zero otherwise. It allows that the task may have the capability
  * to override the rules.
  */
-int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a)
+int smk_tskacc(struct task_smack *subject, char *obj_label,
+	       u32 mode, struct smk_audit_info *a)
 {
-	struct task_smack *tsp = current_security();
-	struct smack_known *skp = smk_of_task(tsp);
+	struct smack_known *skp = smk_of_task(subject);
 	int may;
 	int rc;
 
@@ -212,7 +220,7 @@ int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a)
 		 * it can further restrict access.
 		 */
 		may = smk_access_entry(skp->smk_known, obj_label,
-					&tsp->smk_rules);
+					&subject->smk_rules);
 		if (may < 0)
 			goto out_audit;
 		if ((mode & may) == mode)
@@ -234,6 +242,24 @@ out_audit:
 	return rc;
 }
 
+/**
+ * smk_curacc - determine if current has a specific access to an object
+ * @obj_label: a pointer to the object's Smack label
+ * @mode: the access requested, in "MAY" format
+ * @a : common audit data
+ *
+ * This function checks the current subject label/object label pair
+ * in the access rule list and returns 0 if the access is permitted,
+ * non zero otherwise. It allows that current may have the capability
+ * to override the rules.
+ */
+int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a)
+{
+	struct task_smack *tsp = current_security();
+
+	return smk_tskacc(tsp, obj_label, mode, a);
+}
+
 #ifdef CONFIG_AUDIT
 /**
  * smack_str_from_perm : helper to transalate an int to a
@@ -245,6 +271,7 @@ out_audit:
 static inline void smack_str_from_perm(char *string, int access)
 {
 	int i = 0;
+
 	if (access & MAY_READ)
 		string[i++] = 'r';
 	if (access & MAY_WRITE)
@@ -255,6 +282,8 @@ static inline void smack_str_from_perm(char *string, int access)
 		string[i++] = 'a';
 	if (access & MAY_TRANSMUTE)
 		string[i++] = 't';
+	if (access & MAY_LOCK)
+		string[i++] = 'l';
 	string[i] = '\0';
 }
 /**
@@ -275,7 +304,10 @@ static void smack_log_callback(struct audit_buffer *ab, void *a)
 	audit_log_untrustedstring(ab, sad->subject);
 	audit_log_format(ab, " object=");
 	audit_log_untrustedstring(ab, sad->object);
-	audit_log_format(ab, " requested=%s", sad->request);
+	if (sad->request[0] == '\0')
+		audit_log_format(ab, " labels_differ");
+	else
+		audit_log_format(ab, " requested=%s", sad->request);
 }
 
 /**