commit e84295c46eb56b29f8abb6d07f27c53cc2a74a32
Author: Jiri Slaby <ku@bellona.localdomain>
Date:   Fri Jun 22 14:53:57 2007 +0200

    check for null rates

diff --git a/ath/if_ath_pci.c b/ath/if_ath_pci.c
index 6a65fe7..4c6bfcc 100644
--- a/ath/if_ath_pci.c
+++ b/ath/if_ath_pci.c
@@ -272,6 +272,9 @@ static inline unsigned int ath_copy_rates(struct ieee80211_rate *rates,
 {
 	unsigned int i;
 
+	if (rt == NULL)
+		return 0;
+
 	for (i = 0; i < rt->rate_count; i++, rates++) {
 		rates->rate = rt->rates[i].rate_kbps / 100;
 		rates->val = rt->rates[i].rate_code;