[PATCH 6.18 106/175] wifi: mac80211: correctly check if CSA is active

Greg Kroah-Hartman
2026-02-09T14:31:00Z

From: Miri Korenblit <miriam.rachel.korenblit@intel.com>

[ Upstream commit db1d0b6ab11f612ea8a327663a578c8946efeee9 ]

We are not adding an interface if an existing one is doing CSA.
But the check won't work for MLO station interfaces, since for those,
vif->bss_conf is zeroed out.
Fix this by checking if any link of the vif has an active CSA.

Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20260111191912.7ceff62fc561.Ia38d27f42684d1cfd82d930d232bd5dea6ab9282@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/mac80211/iface.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 0ca55b9655a7f..72c129478da08 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -350,6 +350,8 @@ static int ieee80211_check_concurrent_iface(struct ieee80211_sub_if_data *sdata,
/* we hold the RTNL here so can safely walk the list */
list_for_each_entry(nsdata, &local->interfaces, list) {
if (nsdata != sdata && ieee80211_sdata_running(nsdata)) {
+ struct ieee80211_link_data *link;
+
/*
* Only OCB and monitor mode may coexist
*/
@@ -376,8 +378,10 @@ static int ieee80211_check_concurrent_iface(struct ieee80211_sub_if_data *sdata,
* will not add another interface while any channel
* switch is active.
*/
- if (nsdata->vif.bss_conf.csa_active)
- return -EBUSY;
+ for_each_link_data(nsdata, link) {
+ if (link->conf->csa_active)
+ return -EBUSY;
+ }

/*
* The remaining checks are only performed for interfaces
--
2.51.0