2023-12-19 17:53:08

by Jouni Malinen

[permalink] [raw]
Subject: [PATCH] wifi: mac80211: Skip association timeout update after comeback rejection

From: Jouni Malinen <[email protected]>

It is possible for the TX status report for the (Re)Association Request
frame to be delayed long enough for the AP's (Re)Association Response
frame to be received and processed before it. If that were to happen for
a case where the AP rejects the association with indication to come back
later, the association timeout and retry state should not be modified
anymore with the TX status information that would be processed after
this. Updating the association timeout in such a reverse order of events
could result in shortening the timeouts for the association comeback
mechanism and that could result in the association failing.

Track whether we have already processed association rejection with
comeback time and if so, skip the timeout and retry update on any
following TX status report.

Signed-off-by: Jouni Malinen <[email protected]>
---
net/mac80211/ieee80211_i.h | 1 +
net/mac80211/mlme.c | 11 +++++++++++
2 files changed, 12 insertions(+)

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index cd483787f795..32b7d3f6b4b4 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -439,6 +439,7 @@ struct ieee80211_mgd_assoc_data {
bool need_beacon;
bool synced;
bool timeout_started;
+ bool comeback; /* whether the AP has requested association comeback */
bool s1g;

unsigned int assoc_link_id;
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index a693ca2cf8cd..0c7ce022d2ed 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -5381,6 +5381,7 @@ static void ieee80211_rx_mgmt_assoc_resp(struct ieee80211_sub_if_data *sdata,
assoc_data->ap_addr, tu, ms);
assoc_data->timeout = jiffies + msecs_to_jiffies(ms);
assoc_data->timeout_started = true;
+ assoc_data->comeback = true;
if (ms > IEEE80211_ASSOC_TIMEOUT)
run_again(sdata, assoc_data->timeout);
goto notify_driver;
@@ -6718,8 +6719,18 @@ void ieee80211_sta_work(struct ieee80211_sub_if_data *sdata)
}
ifmgd->auth_data->timeout_started = true;
} else if (ifmgd->assoc_data &&
+ !ifmgd->assoc_data->comeback &&
(ieee80211_is_assoc_req(fc) ||
ieee80211_is_reassoc_req(fc))) {
+ /*
+ * Update association timeout based on the TX status
+ * for the (Re)Association Request frame. Skip this if
+ * we have already processed a (Re)Association Response
+ * frame that indicated need for association comeback
+ * at a specific time in the future. This could happen
+ * if the TX status information is delayed enough for
+ * the response to be received and processed first.
+ */
if (status_acked) {
ifmgd->assoc_data->timeout =
jiffies + IEEE80211_ASSOC_TIMEOUT_SHORT;
--
2.34.1