mac80211: don't try to do anything on unchanged genIE

When the genIE hasn't changed there's no reason to kick
the state machine since it won't be able to do anything
new -- doing this decreases the useless work we do for
reassociating because if we do kick the state machine
it will try to find a usable BSS but there might not be
one because wpa_supplicant will only change the BSSID
a little later.

In a sense this is a workaround for userspace behaviour,
but on the other hand userspace cannot really keep track
of what the kernel currently has for genIE since any
process could have changed that while wpa_supplicant
wasn't looking.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 54a2a1db98a3561df0fc53de454509b8fa2fa497..87743e47a05f06fce5efeee8d6c9d8a8a7061ffc 100644 (file)
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -2492,6 +2492,13 @@ int ieee80211_sta_set_extra_ie(struct ieee80211_sub_if_data *sdata,
 {
        struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 
+       if (len == 0 && ifmgd->extra_ie_len == 0)
+               return -EALREADY;
+
+       if (len == ifmgd->extra_ie_len && ifmgd->extra_ie &&
+           memcmp(ifmgd->extra_ie, ie, len) == 0)
+               return -EALREADY;
+
        kfree(ifmgd->extra_ie);
        if (len == 0) {
                ifmgd->extra_ie = NULL;

diff --git a/net/mac80211/wext.c b/net/mac80211/wext.c
index c14394744a9c321b3a2b73d26d448c8bd7242361..a01154e127f07b0ae6d949177f4dd06c49806667 100644 (file)
--- a/net/mac80211/wext.c
+++ b/net/mac80211/wext.c
@@ -37,12 +37,13 @@ static int ieee80211_ioctl_siwgenie(struct net_device *dev,
 
        if (sdata->vif.type == NL80211_IFTYPE_STATION) {
                int ret = ieee80211_sta_set_extra_ie(sdata, extra, data->length);
-               if (ret)
+               if (ret && ret != -EALREADY)
                        return ret;
                sdata->u.mgd.flags &= ~IEEE80211_STA_AUTO_BSSID_SEL;
                sdata->u.mgd.flags &= ~IEEE80211_STA_EXT_SME;
                sdata->u.mgd.flags &= ~IEEE80211_STA_CONTROL_PORT;
-               ieee80211_sta_req_auth(sdata);
+               if (ret != -EALREADY)
+                       ieee80211_sta_req_auth(sdata);
                return 0;
        }