apparmor: fix invalid reference on profile->disconnected

profile->disconnected was storing an invalid reference to the
disconnected path. Fix it by duplicating the string using
aa_unpack_strdup and freeing accordingly.

Fixes: 72c8a768 ("apparmor: allow profiles to provide info to disconnected paths")
Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

security/apparmor/policy.c

@@ -255,6 +255,7 @@ void aa_free_profile(struct aa_profile *profile)
 
 	aa_put_ns(profile->ns);
 	kfree_sensitive(profile->rename);
+	kfree_sensitive(profile->disconnected);
 
 	free_attachment(&profile->attach);
 

security/apparmor/policy_unpack.c

@@ -804,7 +804,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 	const char *info = "failed to unpack profile";
 	size_t ns_len;
 	struct rhashtable_params params = { 0 };
-	char *key = NULL;
+	char *key = NULL, *disconnected = NULL;
 	struct aa_data *data;
 	int error = -EPROTO;
 	kernel_cap_t tmpcap;
@@ -870,7 +870,8 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 	}
 
 	/* disconnected attachment string is optional */
-	(void) aa_unpack_str(e, &profile->disconnected, "disconnected");
+	(void) aa_unpack_strdup(e, &disconnected, "disconnected");
+	profile->disconnected = disconnected;
 
 	/* per profile debug flags (complain, audit) */
 	if (!aa_unpack_nameX(e, AA_STRUCT, "flags")) {