cfg80211/mac80211: improve ad-hoc multicast rate handling

- store the multicast rate as an index instead of the rate value
  (reduces cpu overhead in a hotpath)
- validate the rate values (must match a bitrate in at least one sband)

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 6fe6837dc134..410d104b1347 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -915,7 +915,8 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
 
         sdata->u.ibss.privacy = params->privacy;
         sdata->u.ibss.basic_rates = params->basic_rates;
-        sdata->vif.bss_conf.mcast_rate = params->mcast_rate;
+        memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
+               sizeof(params->mcast_rate));
 
         sdata->vif.bss_conf.beacon_int = params->beacon_interval;