From e8e599a635066c50ac214c3e10858f1d37e03022 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Tue, 19 Sep 2023 08:34:15 +0200 Subject: [PATCH] wifi: mac80211: fix potential key use-after-free commit 31db78a4923ef5e2008f2eed321811ca79e7f71b upstream. When ieee80211_key_link() is called by ieee80211_gtk_rekey_add() but returns 0 due to KRACK protection (identical key reinstall), ieee80211_gtk_rekey_add() will still return a pointer into the key, in a potential use-after-free. This normally doesn't happen since it's only called by iwlwifi in case of WoWLAN rekey offload which has its own KRACK protection, but still better to fix, do that by returning an error code and converting that to success on the cfg80211 boundary only, leaving the error for bad callers of ieee80211_gtk_rekey_add(). Reported-by: Dan Carpenter Fixes: fdf7cb4185b6 ("mac80211: accept key reinstall without changing anything") Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin [ Sherry: bp to fix CVE-2023-52530, resolved minor conflicts in net/mac80211/cfg.c because of context change due to missing commit 23a5f0af6ff4 ("wifi: mac80211: remove cipher scheme support") ccdde7c74ffd ("wifi: mac80211: properly implement MLO key handling")] Signed-off-by: Sherry Yang Signed-off-by: Greg Kroah-Hartman --- net/mac80211/cfg.c | 3 +++ net/mac80211/key.c | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 0c3da7771b48..c8d2fe8fbc0a 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -509,6 +509,9 @@ static int ieee80211_add_key(struct wiphy *wiphy, struct net_device *dev, sta->cipher_scheme = cs; err = ieee80211_key_link(key, sdata, sta); + /* KRACK protection, shouldn't happen but just silently accept key */ + if (err == -EALREADY) + err = 0; out_unlock: mutex_unlock(&local->sta_mtx); diff --git a/net/mac80211/key.c b/net/mac80211/key.c index 6a72c33679ba..6b089594a9f3 100644 --- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -843,7 +843,7 @@ int ieee80211_key_link(struct ieee80211_key *key, */ if (ieee80211_key_identical(sdata, old_key, key)) { ieee80211_key_free_unused(key); - ret = 0; + ret = -EALREADY; goto out; }