diff mbox series

[SRU,J/F,1/1] wifi: mac80211: fix potential key use-after-free

Message ID 20240412200217.23419-2-bethany.jamison@canonical.com
State New
Headers show
Series CVE-2023-52530 | expand

Commit Message

Bethany Jamison April 12, 2024, 8:02 p.m. UTC 
From: Johannes Berg <johannes.berg@intel.com>

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@linaro.org>
Fixes: fdf7cb4185b6 ("mac80211: accept key reinstall without changing anything")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
(backported from commit 31db78a4923ef5e2008f2eed321811ca79e7f71b)
[bjamison: context conflict - added KRACK protection as written in the fix
commit since the context conflict was with a neighboring line that doesn't
affect the fix commit]
CVE-2023-52530
Signed-off-by: Bethany Jamison <bethany.jamison@canonical.com>
---
 net/mac80211/cfg.c | 3 +++
 net/mac80211/key.c | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 02bd90a537058..0e383beaf723f 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -511,6 +511,9 @@  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 f695fc80088bc..7b427e39831bd 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;
 	}