This is a note to let you know that I've just added the patch titled
wifi: mac80211: fix potential key use-after-free
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-mac80211-fix-potential-key-use-after-free.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 f5f82238f8d774751dea488297257f5ab91b6764
Author: Johannes Berg <johannes.berg@xxxxxxxxx>
Date: Tue Sep 19 08:34:15 2023 +0200
wifi: mac80211: fix potential key use-after-free
[ Upstream commit 31db78a4923ef5e2008f2eed321811ca79e7f71b ]
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 <dan.carpenter@xxxxxxxxxx>
Fixes: fdf7cb4185b6 ("mac80211: accept key reinstall without changing anything")
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index cf3453b532d67..0167413d56972 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -566,6 +566,9 @@ static int ieee80211_add_key(struct wiphy *wiphy, struct net_device *dev,
}
err = ieee80211_key_link(key, link, 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 e8f6c1e5eabfc..23bb24243c6e9 100644
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -901,7 +901,7 @@ 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;
}
