| From cb150b9d23be6ee7f3a0fff29784f1c5b5ac514d Mon Sep 17 00:00:00 2001 |
| From: Johannes Berg <johannes.berg@intel.com> |
| Date: Wed, 27 Jan 2016 13:29:34 +0100 |
| Subject: cfg80211/wext: fix message ordering |
| |
| From: Johannes Berg <johannes.berg@intel.com> |
| |
| commit cb150b9d23be6ee7f3a0fff29784f1c5b5ac514d upstream. |
| |
| Since cfg80211 frequently takes actions from its netdev notifier |
| call, wireless extensions messages could still be ordered badly |
| since the wext netdev notifier, since wext is built into the |
| kernel, runs before the cfg80211 netdev notifier. For example, |
| the following can happen: |
| |
| 5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default |
| link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff |
| 5: wlan1: <BROADCAST,MULTICAST,UP> |
| link/ether |
| |
| when setting the interface down causes the wext message. |
| |
| To also fix this, export the wireless_nlevent_flush() function |
| and also call it from the cfg80211 notifier. |
| |
| Signed-off-by: Johannes Berg <johannes.berg@intel.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| include/net/iw_handler.h | 6 ++++++ |
| net/wireless/core.c | 2 ++ |
| net/wireless/wext-core.c | 3 ++- |
| 3 files changed, 10 insertions(+), 1 deletion(-) |
| |
| --- a/include/net/iw_handler.h |
| +++ b/include/net/iw_handler.h |
| @@ -439,6 +439,12 @@ int dev_get_wireless_info(char *buffer, |
| /* Send a single event to user space */ |
| void wireless_send_event(struct net_device *dev, unsigned int cmd, |
| union iwreq_data *wrqu, const char *extra); |
| +#ifdef CONFIG_WEXT_CORE |
| +/* flush all previous wext events - if work is done from netdev notifiers */ |
| +void wireless_nlevent_flush(void); |
| +#else |
| +static inline void wireless_nlevent_flush(void) {} |
| +#endif |
| |
| /* We may need a function to send a stream of events to user space. |
| * More on that later... */ |
| --- a/net/wireless/core.c |
| +++ b/net/wireless/core.c |
| @@ -1147,6 +1147,8 @@ static int cfg80211_netdev_notifier_call |
| return NOTIFY_DONE; |
| } |
| |
| + wireless_nlevent_flush(); |
| + |
| return NOTIFY_OK; |
| } |
| |
| --- a/net/wireless/wext-core.c |
| +++ b/net/wireless/wext-core.c |
| @@ -342,7 +342,7 @@ static const int compat_event_type_size[ |
| |
| /* IW event code */ |
| |
| -static void wireless_nlevent_flush(void) |
| +void wireless_nlevent_flush(void) |
| { |
| struct sk_buff *skb; |
| struct net *net; |
| @@ -355,6 +355,7 @@ static void wireless_nlevent_flush(void) |
| GFP_KERNEL); |
| } |
| } |
| +EXPORT_SYMBOL_GPL(wireless_nlevent_flush); |
| |
| static int wext_netdev_notifier_call(struct notifier_block *nb, |
| unsigned long state, void *ptr) |