[PATCH 4.19 044/321] mac80211: fix station inactive_time shortly after boot

Greg Kroah-Hartman
2019-12-03T22:48:42Z

From: Ahmed Zaki <anzaki@gmail.com>

[ Upstream commit 285531f9e6774e3be71da6673d475ff1a088d675 ]

In the first 5 minutes after boot (time of INITIAL_JIFFIES),
ieee80211_sta_last_active() returns zero if last_ack is zero. This
leads to "inactive time" showing jiffies_to_msecs(jiffies).

# iw wlan0 station get fc:ec:da:64:a6:dd
Station fc:ec:da:64:a6:dd (on wlan0)
inactive time: 4294894049 ms
.
.
connected time: 70 seconds

Fix by returning last_rx if last_ack == 0.

Signed-off-by: Ahmed Zaki <anzaki@gmail.com>
Link: https://lore.kernel.org/r/20191031121243.27694-1-anzaki@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/mac80211/sta_info.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index f34202242d24d..507409e3fd39c 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -2356,7 +2356,8 @@ unsigned long ieee80211_sta_last_active(struct sta_info *sta)
{
struct ieee80211_sta_rx_stats *stats = sta_get_last_rx_stats(sta);

- if (time_after(stats->last_rx, sta->status_stats.last_ack))
+ if (!sta->status_stats.last_ack ||
+ time_after(stats->last_rx, sta->status_stats.last_ack))
return stats->last_rx;
return sta->status_stats.last_ack;
}
--
2.20.1