ieee1394: nodemgr: fix leak of struct csr1212_keyval

csr1212_keep_keyval(kv) in nodemgr_process_root_directory was
unbalanced if ne->vendor_name_kv already exists.  This happens for
example if eth1394 or raw1394 modify the local config ROM and it is
parsed again.

As a bonus, the attempt to add the vendor_name_kv sysfs attribute
when it already exists is now fixed for good.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/ieee1394/nodemgr.c

@@ -1112,7 +1112,7 @@ static void nodemgr_process_root_directory(struct host_info *hi, struct node_ent
 {
 	unsigned int ud_id = 0;
 	struct csr1212_dentry *dentry;
-	struct csr1212_keyval *kv;
+	struct csr1212_keyval *kv, *vendor_name_kv = NULL;
 	u8 last_key_id = 0;
 
 	ne->needs_probe = 0;
@@ -1139,8 +1139,8 @@ static void nodemgr_process_root_directory(struct host_info *hi, struct node_ent
 				    CSR1212_TEXTUAL_DESCRIPTOR_LEAF_WIDTH(kv) == 0 &&
 				    CSR1212_TEXTUAL_DESCRIPTOR_LEAF_CHAR_SET(kv) == 0 &&
 				    CSR1212_TEXTUAL_DESCRIPTOR_LEAF_LANGUAGE(kv) == 0) {
-					ne->vendor_name_kv = kv;
 					csr1212_keep_keyval(kv);
+					vendor_name_kv = kv;
 				}
 			}
 			break;
@@ -1149,10 +1149,13 @@ static void nodemgr_process_root_directory(struct host_info *hi, struct node_ent
 	}
 
 	if (ne->vendor_name_kv) {
-		int error = device_create_file(&ne->device,
-					       &dev_attr_ne_vendor_name_kv);
-
-		if (error && error != -EEXIST)
+		kv = ne->vendor_name_kv;
+		ne->vendor_name_kv = vendor_name_kv;
+		csr1212_release_keyval(kv);
+	} else if (vendor_name_kv) {
+		ne->vendor_name_kv = vendor_name_kv;
+		if (device_create_file(&ne->device,
+				       &dev_attr_ne_vendor_name_kv) != 0)
 			HPSB_ERR("Failed to add sysfs attribute");
 	}
 }