[PATCH 4.19 17/38] mac80211: fix station rate table updates on assoc

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Felix Fietkau <nbd@nbd.name>

commit 18fe0fae61252b5ae6e26553e2676b5fac555951 upstream.

If the driver uses .sta_add, station entries are only uploaded after the sta
is in assoc state. Fix early station rate table updates by deferring them
until the sta has been uploaded.

Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20210201083324.3134-1-nbd@nbd.name
[use rcu_access_pointer() instead since we won't dereference here]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/mac80211/driver-ops.c |    5 ++++-
 net/mac80211/rate.c       |    3 ++-
 2 files changed, 6 insertions(+), 2 deletions(-)

--- a/net/mac80211/driver-ops.c
+++ b/net/mac80211/driver-ops.c
@@ -128,8 +128,11 @@ int drv_sta_state(struct ieee80211_local
 	} else if (old_state == IEEE80211_STA_AUTH &&
 		   new_state == IEEE80211_STA_ASSOC) {
 		ret = drv_sta_add(local, sdata, &sta->sta);
-		if (ret == 0)
+		if (ret == 0) {
 			sta->uploaded = true;
+			if (rcu_access_pointer(sta->sta.rates))
+				drv_sta_rate_tbl_update(local, sdata, &sta->sta);
+		}
 	} else if (old_state == IEEE80211_STA_ASSOC &&
 		   new_state == IEEE80211_STA_AUTH) {
 		drv_sta_remove(local, sdata, &sta->sta);
--- a/net/mac80211/rate.c
+++ b/net/mac80211/rate.c
@@ -941,7 +941,8 @@ int rate_control_set_rates(struct ieee80
 	if (old)
 		kfree_rcu(old, rcu_head);
 
-	drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta);
+	if (sta->uploaded)
+		drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta);
 
 	ieee80211_sta_set_expected_throughput(pubsta, sta_get_expected_throughput(sta));