This is a note to let you know that I've just added the patch titled wifi: cfg80211: fix RCU dereference in __cfg80211_bss_update to the 6.1-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-cfg80211-fix-rcu-dereference-in-__cfg80211_bss_.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e51bbba7d8a26f0f1a38406ed34f6bc2ddc4f7ef Author: Edward Adam Davis <eadavis@xxxxxx> Date: Wed Jan 3 20:13:51 2024 +0800 wifi: cfg80211: fix RCU dereference in __cfg80211_bss_update [ Upstream commit 1184950e341c11b6f82bc5b59564411d9537ab27 ] Replace rcu_dereference() with rcu_access_pointer() since we hold the lock here (and aren't in an RCU critical section). Fixes: 32af9a9e1069 ("wifi: cfg80211: free beacon_ies when overridden from hidden BSS") Reported-and-tested-by: syzbot+864a269c27ee06b58374@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Edward Adam Davis <eadavis@xxxxxx> Link: https://msgid.link/tencent_BF8F0DF0258C8DBF124CDDE4DD8D992DCF07@xxxxxx Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 86906557a04e..3ad4c1032c03 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -1811,7 +1811,7 @@ cfg80211_bss_update(struct cfg80211_registered_device *rdev, &hidden->hidden_list); hidden->refcount++; - ies = (void *)rcu_dereference(new->pub.beacon_ies); + ies = (void *)rcu_access_pointer(new->pub.beacon_ies); rcu_assign_pointer(new->pub.beacon_ies, hidden->pub.beacon_ies); if (ies)