device: Fix invalid read in att_connect_cb

We should keep a reference to GIOChannel created in att_connect so we
can properly shut it down if the device is removed during a connection
attempt. After establishing the connection, we drop the GIOChannel
reference because GAttrib will take the responsability of disconnect the
link based on the registered ATTIO connection callbacks.

This patch fixes the following invalid read reported by valgrind when
the device is removed and we have a ongoing connection attempt:

Invalid read of size 4
   at 0x1A90D8: att_connect_cb (device.c:1712)
   by 0x17EDB9: connect_cb (btio.c:169)
   by 0x4E6E29C: g_main_context_dispatch (in /usr/lib/libglib-2.0.so.0.2800.8)
   by 0x4E6EA77: ??? (in /usr/lib/libglib-2.0.so.0.2800.8)
   by 0x4E6F0B9: g_main_loop_run (in /usr/lib/libglib-2.0.so.0.2800.8)
   by 0x18ACB3: main (main.c:485)
 Address 0x68aacb8 is 456 bytes inside a block of size 472 free'd
   at 0x4C2556E: free (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
   by 0x1A596B: device_free (device.c:248)
   by 0x121EB5: remove_interface (object.c:563)
   by 0x122288: g_dbus_unregister_interface (object.c:715)
   by 0x1AAFD8: btd_device_unref (device.c:2636)
   by 0x1A7912: device_remove (device.c:1058)
   by 0x19F371: adapter_remove_device (adapter.c:1122)
   by 0x1A0AD4: remove_device (adapter.c:1720)
   by 0x1214C4: process_message (object.c:224)
   by 0x121B60: generic_message (object.c:447)
   by 0x51348C0: ??? (in /usr/lib/libdbus-1.so.3.5.7)
   by 0x512679F: dbus_connection_dispatch (in /usr/lib/libdbus-1.so.3.5.7)

diff --git a/src/device.c b/src/device.c
index 311dca1..36d07ca 100644 (file)
--- a/src/device.c
+++ b/src/device.c
@@ -160,6 +160,8 @@ struct btd_device {
 
        gboolean        authorizing;
        gint            ref;
+
+       GIOChannel      *att_io;
 };
 
 static uint16_t uuid_list[] = {
@@ -247,6 +249,11 @@ static void device_free(gpointer user_data)
        if (device->auto_id)
                g_source_remove(device->auto_id);
 
+       if (device->att_io) {
+               g_io_channel_shutdown(device->att_io, FALSE, NULL);
+               g_io_channel_unref(device->att_io);
+       }
+
        DBG("%p", device);
 
        g_free(device->authr);
@@ -1820,6 +1827,9 @@ static void att_connect_cb(GIOChannel *io, GError *gerr, gpointer user_data)
        struct btd_device *device = user_data;
        GAttrib *attrib;
 
+       g_io_channel_unref(device->att_io);
+       device->att_io = NULL;
+
        if (gerr) {
                DBG("%s", gerr->message);
 
@@ -1885,7 +1895,7 @@ static gboolean att_connect(gpointer user_data)
                return FALSE;
        }
 
-       g_io_channel_unref(io);
+       device->att_io = io;
 
        return FALSE;
 }