mac80211: fix last RX rate data consistency
When storing the last_rate_* values in the RX code, there's nothing
to guarantee consistency, so a concurrent reader could see, e.g.
last_rate_idx on the new value, but last_rate_flag still on the old,
getting completely bogus values in the end.
To fix this, I lifted the sta_stats_encode_rate() function from my
old rate statistics code, which encodes the entire rate data into a
single 16-bit value, avoiding the consistency issue.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index d14c66d..5a6c36c 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1421,16 +1421,9 @@
test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
sta->rx_stats.last_rx = jiffies;
if (ieee80211_is_data(hdr->frame_control) &&
- !is_multicast_ether_addr(hdr->addr1)) {
- sta->rx_stats.last_rate_idx =
- status->rate_idx;
- sta->rx_stats.last_rate_flag =
- status->flag;
- sta->rx_stats.last_rate_vht_flag =
- status->vht_flag;
- sta->rx_stats.last_rate_vht_nss =
- status->vht_nss;
- }
+ !is_multicast_ether_addr(hdr->addr1))
+ sta->rx_stats.last_rate =
+ sta_stats_encode_rate(status);
}
} else if (rx->sdata->vif.type == NL80211_IFTYPE_OCB) {
sta->rx_stats.last_rx = jiffies;
@@ -1440,12 +1433,8 @@
* match the current local configuration when processed.
*/
sta->rx_stats.last_rx = jiffies;
- if (ieee80211_is_data(hdr->frame_control)) {
- sta->rx_stats.last_rate_idx = status->rate_idx;
- sta->rx_stats.last_rate_flag = status->flag;
- sta->rx_stats.last_rate_vht_flag = status->vht_flag;
- sta->rx_stats.last_rate_vht_nss = status->vht_nss;
- }
+ if (ieee80211_is_data(hdr->frame_control))
+ sta->rx_stats.last_rate = sta_stats_encode_rate(status);
}
if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)