From a7a206b8e2324c75c006a2cf57e57201cfaab815 Mon Sep 17 00:00:00 2001
From: Beniamino Galvani <bgalvani@redhat.com>
Date: Wed, 6 Jul 2016 17:59:08 +0200
Subject: [PATCH] platform: wifi: drop old wifi data when an interface is
 renamed

Drop the old wifi data when the interface is renamed, otherwise WEXT
methods would use the old name.

https://bugzilla.gnome.org/show_bug.cgi?id=768433
(cherry picked from commit 45484af2afd33cf1b0846c8e6f81f055e64568fd)
---
 src/platform/nm-linux-platform.c | 23 ++++++++++++++++++++---
 src/platform/wifi/wifi-utils.c   | 16 ++++++++++++++++
 src/platform/wifi/wifi-utils.h   |  4 ++++
 3 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/src/platform/nm-linux-platform.c b/src/platform/nm-linux-platform.c
index 1f4e36f730..f6f7be8004 100644
--- a/src/platform/nm-linux-platform.c
+++ b/src/platform/nm-linux-platform.c
@@ -5154,13 +5154,30 @@ static WifiData *
 wifi_get_wifi_data (NMPlatform *platform, int ifindex)
 {
 	NMLinuxPlatformPrivate *priv = NM_LINUX_PLATFORM_GET_PRIVATE (platform);
+	const NMPlatformLink *pllink;
 	WifiData *wifi_data;
 
 	wifi_data = g_hash_table_lookup (priv->wifi_data, GINT_TO_POINTER (ifindex));
-	if (!wifi_data) {
-		const NMPlatformLink *pllink;
+	pllink = nm_platform_link_get (platform, ifindex);
 
-		pllink = nm_platform_link_get (platform, ifindex);
+	/* @wifi_data contains an interface name which is used for WEXT queries. If
+	 * the interface name changes we should at least replace the name in the
+	 * existing structure; but probably a complete reinitialization is better
+	 * because during the initial creation there can be race conditions while
+	 * the interface is renamed by udev.
+	 */
+	if (wifi_data && pllink) {
+		if (!nm_streq (wifi_utils_get_iface (wifi_data), pllink->name)) {
+			_LOGD ("wifi: interface %s renamed to %s, dropping old data for ifindex %d",
+			       wifi_utils_get_iface (wifi_data),
+			       pllink->name,
+			       ifindex);
+			g_hash_table_remove (priv->wifi_data, GINT_TO_POINTER (ifindex));
+			wifi_data = NULL;
+		}
+	}
+
+	if (!wifi_data) {
 		if (pllink) {
 			if (pllink->type == NM_LINK_TYPE_WIFI)
 				wifi_data = wifi_utils_init (pllink->name, ifindex, TRUE);
diff --git a/src/platform/wifi/wifi-utils.c b/src/platform/wifi/wifi-utils.c
index 38e5a0545e..4f04041a2d 100644
--- a/src/platform/wifi/wifi-utils.c
+++ b/src/platform/wifi/wifi-utils.c
@@ -70,6 +70,22 @@ wifi_utils_init (const char *iface, int ifindex, gboolean check_scan)
 	return ret;
 }
 
+int
+wifi_utils_get_ifindex (WifiData *data)
+{
+	g_return_val_if_fail (data != NULL, -1);
+
+	return data->ifindex;
+}
+
+const char *
+wifi_utils_get_iface (WifiData *data)
+{
+	g_return_val_if_fail (data != NULL, NULL);
+
+	return data->iface;
+}
+
 NMDeviceWifiCapabilities
 wifi_utils_get_caps (WifiData *data)
 {
diff --git a/src/platform/wifi/wifi-utils.h b/src/platform/wifi/wifi-utils.h
index 21dac9e9cc..9555bbeece 100644
--- a/src/platform/wifi/wifi-utils.h
+++ b/src/platform/wifi/wifi-utils.h
@@ -33,6 +33,10 @@ gboolean wifi_utils_is_wifi (const char *iface, const char *sysfs_path);
 
 WifiData *wifi_utils_init (const char *iface, int ifindex, gboolean check_scan);
 
+int wifi_utils_get_ifindex (WifiData *data);
+
+const char *wifi_utils_get_iface (WifiData *data);
+
 void wifi_utils_deinit (WifiData *data);
 
 NMDeviceWifiCapabilities wifi_utils_get_caps (WifiData *data);