From 9b55d5c1f5e481e391957f9096d798ca331c461b Mon Sep 17 00:00:00 2001 From: Michael Bommarito Date: Tue, 21 Apr 2026 20:06:51 -0400 Subject: [PATCH] wifi: mac80211: check ieee80211_rx_data_set_link return in pubsta MLO path __ieee80211_rx_handle_packet() resolves the link via ieee80211_rx_data_set_link() on the pubsta->mlo path but ignores the helper's return value. Inside the helper, rx->link = rcu_dereference(rx->sdata->link[link_id]); can leave rx->link NULL if link_id references a slot already cleared by ieee80211_vif_set_links() during station-initiated ML reconfiguration (see mlme.c's ieee80211_ml_reconfiguration(), which invalidates sdata->link[] before the matching ieee80211_sta_remove_link() loop walks the link-sta hash). RX dispatch still resolves a link_sta from the hash and then drops into ieee80211_prepare_and_rx_handle(), which dereferences link->conf->addr. Every other user site of ieee80211_rx_data_set_link() checks the return and bails on failure; only this branch did not. Mirror the safe pattern. Fixes: e66b7920aa5a ("wifi: mac80211: fix initialization of rx->link and rx->link_sta") Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito Link: https://patch.msgid.link/20260422000651.4184602-1-michael.bommarito@gmail.com Signed-off-by: Johannes Berg --- net/mac80211/rx.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 3e5d1c47a5b06..5a92413a911f2 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -5380,7 +5380,9 @@ static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, if (!link_sta) goto out; - ieee80211_rx_data_set_link(&rx, link_sta->link_id); + if (!ieee80211_rx_data_set_link(&rx, + link_sta->link_id)) + goto out; } if (ieee80211_prepare_and_rx_handle(&rx, skb, true)) -- 2.47.3