From: Johannes Berg <johannes.berg@intel.com>
Date: Wed, 5 Oct 2022 21:24:10 +0200
Subject: [PATCH] wifi: mac80211: fix crash in beacon protection for P2P-device
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Patch-mainline: Not yet, embargoed
References: CVE-2022-42722 bsc#1204125
If beacon protection is active but the beacon cannot be
decrypted or is otherwise malformed, we call the cfg80211
API to report this to userspace, but that uses a netdev
pointer, which isn't present for P2P-Device. Fix this to
call it only conditionally to ensure cfg80211 won't crash
in the case of P2P-Device.
This fixes CVE-2022-42722.
Reported-by: Sönke Huster <shuster@seemoo.tu-darmstadt.de>
Fixes: 9eaf183af741 ("mac80211: Report beacon protection failures to user space")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
net/mac80211/rx.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index bd215fe3c796..6001adc0a00e 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1978,10 +1978,11 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
if (mmie_keyidx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS ||
mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS +
- NUM_DEFAULT_BEACON_KEYS) {
- cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
- skb->data,
- skb->len);
+ NUM_DEFAULT_BEACON_KEYS) {
+ if (rx->sdata->dev)
+ cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
+ skb->data,
+ skb->len);
return RX_DROP_MONITOR; /* unexpected BIP keyidx */
}
@@ -2131,7 +2132,8 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
/* either the frame has been decrypted or will be dropped */
status->flag |= RX_FLAG_DECRYPTED;
- if (unlikely(ieee80211_is_beacon(fc) && result == RX_DROP_UNUSABLE))
+ if (unlikely(ieee80211_is_beacon(fc) && result == RX_DROP_UNUSABLE &&
+ rx->sdata->dev))
cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
skb->data, skb->len);
--
2.35.3