From ab007a449638eeacaf6f626b707842af5274db95 Mon Sep 17 00:00:00 2001
From: Aleksander Morgado <aleksander@aleksander.es>
Date: Thu, 18 Mar 2021 11:20:02 +0100
Subject: [PATCH] base-modem: plug leaks when organizing ports

The GLists maintained in the logic need to be explicitly freed (just
the lists, not the list contents) if we exit early on error or if we
end up deciding that the specific ports are available but unsupported
by the plugin (e.g. if a plugin that doesn't support net ports finds
net ports in the modem).

  ==225333== 24 bytes in 1 blocks are definitely lost in loss record 2,024 of 5,525
  ==225333==    at 0x483E77F: malloc (vg_replace_malloc.c:307)
  ==225333==    by 0x506C539: g_malloc (in /usr/lib/libglib-2.0.so.0.6600.7)
  ==225333==    by 0x508DC8F: g_slice_alloc (in /usr/lib/libglib-2.0.so.0.6600.7)
  ==225333==    by 0x50636B4: g_list_append (in /usr/lib/libglib-2.0.so.0.6600.7)
  ==225333==    by 0x17E671: mm_base_modem_organize_ports (mm-base-modem.c:1298)
  ==225333==    by 0x1E4409: mm_plugin_create_modem (mm-plugin.c:1094)
  ==225333==    by 0x162C81: mm_device_create_modem (mm-device.c:481)
  ==225333==    by 0x15DE60: device_support_check_ready (mm-base-manager.c:218)
  ==225333==    by 0x4EA8173: ??? (in /usr/lib/libgio-2.0.so.0.6600.7)
  ==225333==    by 0x4EAC6E8: ??? (in /usr/lib/libgio-2.0.so.0.6600.7)
  ==225333==    by 0x16730F: device_context_run_ready (mm-plugin-manager.c:1533)
  ==225333==    by 0x4EA8173: ??? (in /usr/lib/libgio-2.0.so.0.6600.7)
---
 src/mm-base-modem.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/src/mm-base-modem.c b/src/mm-base-modem.c
index bb2e51dd..ad34ab1d 100644
--- a/src/mm-base-modem.c
+++ b/src/mm-base-modem.c
@@ -1177,15 +1177,17 @@ mm_base_modem_organize_ports (MMBaseModem *self,
     MMPortSerialGps *gps = NULL;
     MMPortSerial *audio = NULL;
     MMPortSerialAt *data_at_primary = NULL;
-    GList *data_at = NULL;
-    GList *data_net = NULL;
+    GList *l;
+    /* These lists don't keep full references, so they should be
+     * g_list_free()-ed on error exits */
+    g_autoptr(GList) data_at = NULL;
+    g_autoptr(GList) data_net = NULL;
 #if defined WITH_QMI
-    GList *qmi = NULL;
+    g_autoptr(GList) qmi = NULL;
 #endif
 #if defined WITH_MBIM
-    GList *mbim = NULL;
+    g_autoptr(GList) mbim = NULL;
 #endif
-    GList *l;
 
     g_return_val_if_fail (MM_IS_BASE_MODEM (self), FALSE);
 
@@ -1411,7 +1413,7 @@ mm_base_modem_organize_ports (MMBaseModem *self,
     if (data_net) {
         if (self->priv->data_net_supported) {
             g_list_foreach (data_net, (GFunc)g_object_ref, NULL);
-            self->priv->data = g_list_concat (self->priv->data, data_net);
+            self->priv->data = g_list_concat (self->priv->data, g_steal_pointer (&data_net));
         } else
             mm_obj_dbg (self, "net ports available but ignored");
     }
@@ -1424,7 +1426,7 @@ mm_base_modem_organize_ports (MMBaseModem *self,
                 self->priv->data = g_list_append (self->priv->data, g_object_ref (data_at_primary));
             if (data_at) {
                 g_list_foreach (data_at, (GFunc)g_object_ref, NULL);
-                self->priv->data = g_list_concat (self->priv->data, data_at);
+                self->priv->data = g_list_concat (self->priv->data, g_steal_pointer (&data_at));
             }
         } else
             mm_obj_dbg (self, "at data ports available but ignored");
@@ -1451,14 +1453,14 @@ mm_base_modem_organize_ports (MMBaseModem *self,
                             mm_port_peek_kernel_device (
                                 MM_PORT (self->priv->data->data))));
         g_list_foreach (qmi, (GFunc)g_object_ref, NULL);
-        self->priv->qmi = qmi;
+        self->priv->qmi = g_steal_pointer (&qmi);
     }
 #endif
 
 #if defined WITH_MBIM
     if (mbim) {
         g_list_foreach (mbim, (GFunc)g_object_ref, NULL);
-        self->priv->mbim = mbim;
+        self->priv->mbim = g_steal_pointer (&mbim);
     }
 #endif