mac80211: Check rate->idx before rate->count

The drivers are not required to fill in rate->count if rate->idx is set
to -1. Hence, we should first check rate->idx before accessing
rate->count.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index cdb2853..972244f 100644 (file)
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -300,10 +300,10 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
 static bool
 minstrel_ht_txstat_valid(struct ieee80211_tx_rate *rate)
 {
-       if (!rate->count)
+       if (rate->idx < 0)
                return false;
 
-       if (rate->idx < 0)
+       if (!rate->count)
                return false;
 
        return !!(rate->flags & IEEE80211_TX_RC_MCS);