[PATCH AUTOSEL 4.19 2/5] wifi: mac80211: fix race condition on enabling fast-xmit

[Sasha Levin]

From: Felix Fietkau <nbd@xxxxxxxx>

[ Upstream commit bcbc84af1183c8cf3d1ca9b78540c2185cd85e7f ]

fast-xmit must only be enabled after the sta has been uploaded to the driver,
otherwise it could end up passing the not-yet-uploaded sta via drv_tx calls
to the driver, leading to potential crashes because of uninitialized drv_priv
data.
Add a missing sta->uploaded check and re-check fast xmit after inserting a sta.

Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
Link: https://msgid.link/20240104181059.84032-1-nbd@xxxxxxxx
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 net/mac80211/sta_info.c | 2 ++
 net/mac80211/tx.c       | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 5c209f72de70..714d0b01ea62 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -629,6 +629,8 @@ static int sta_info_insert_finish(struct sta_info *sta) __acquires(RCU)
 	if (ieee80211_vif_is_mesh(&sdata->vif))
 		mesh_accept_plinks_update(sdata);
 
+	ieee80211_check_fast_xmit(sta);
+
 	return 0;
  out_remove:
 	sta_info_hash_del(local, sta);
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 3a0aadf881fc..89500b1fe301 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2868,7 +2868,7 @@ void ieee80211_check_fast_xmit(struct sta_info *sta)
 	    sdata->vif.type == NL80211_IFTYPE_STATION)
 		goto out;
 
-	if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED))
+	if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED) || !sta->uploaded)
 		goto out;
 
 	if (test_sta_flag(sta, WLAN_STA_PS_STA) ||
-- 
2.43.0