mac80211: Checking IBSS support while changing channel in ad-hoc mode

This patch adds a check to the set_channel flow. When attempting to change
the channel while in IBSS mode, and the new channel does not support IBSS
mode, the flow return with an error value with no consequences on the
mac80211 and driver state.

Signed-off-by: Assaf Krauss <assaf.krauss@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 11 insertions, 4 deletions

diff --git a/net/mac80211/wext.c b/net/mac80211/wext.c
index 8311bb24f9f3..a8bb8e31b1ec 100644
--- a/net/mac80211/wext.c
+++ b/net/mac80211/wext.c
@@ -290,14 +290,22 @@ static int ieee80211_ioctl_giwmode(struct net_device *dev,
         return 0;
 }
 
-int ieee80211_set_freq(struct ieee80211_local *local, int freqMHz)
+int ieee80211_set_freq(struct net_device *dev, int freqMHz)
 {
         int ret = -EINVAL;
         struct ieee80211_channel *chan;
+        struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 
         chan = ieee80211_get_channel(local->hw.wiphy, freqMHz);
 
         if (chan && !(chan->flags & IEEE80211_CHAN_DISABLED)) {
+                if (sdata->vif.type == IEEE80211_IF_TYPE_IBSS &&
+                    chan->flags & IEEE80211_CHAN_NO_IBSS) {
+                        printk(KERN_DEBUG "%s: IBSS not allowed on frequency "
+                                "%d MHz\n", dev->name, chan->center_freq);
+                        return ret;
+                }
                 local->oper_channel = chan;
 
                 if (local->sta_sw_scanning || local->sta_hw_scanning)
@@ -315,7 +323,6 @@ static int ieee80211_ioctl_siwfreq(struct net_device *dev,
                                    struct iw_request_info *info,
                                    struct iw_freq *freq, char *extra)
 {
-        struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 
         if (sdata->vif.type == IEEE80211_IF_TYPE_STA)
@@ -329,14 +336,14 @@ static int ieee80211_ioctl_siwfreq(struct net_device *dev,
                                         IEEE80211_STA_AUTO_CHANNEL_SEL;
                         return 0;
                 } else
-                        return ieee80211_set_freq(local,
+                        return ieee80211_set_freq(dev,
                                 ieee80211_channel_to_frequency(freq->m));
         } else {
                 int i, div = 1000000;
                 for (i = 0; i < freq->e; i++)
                         div /= 10;
                 if (div > 0)
-                        return ieee80211_set_freq(local, freq->m / div);
+                        return ieee80211_set_freq(dev, freq->m / div);
                 else
                         return -EINVAL;
         }