This is a note to let you know that I've just added the patch titled wifi: mac80211: fix race condition on enabling fast-xmit to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: wifi-mac80211-fix-race-condition-on-enabling-fast-xm.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit a76fd2cce0487ef1c1d83b9fdebbb9bcae6a5de4 Author: Felix Fietkau <nbd@xxxxxxxx> Date: Thu Jan 4 19:10:59 2024 +0100 wifi: mac80211: fix race condition on enabling fast-xmit [ 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> diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 0f97c6fcec174..e330036e02eac 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -683,6 +683,8 @@ 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 8bd01dfa75cb1..5fd9a6f752a1d 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -2919,7 +2919,7 @@ 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) ||