wifi: mt76: mt7996: Fix possible oob access in mt7996_mac_write_txwi_80211()

Check frame length before accessing the mgmt fields in
mt7996_mac_write_txwi_80211 in order to avoid a possible oob access.

Fixes: 98686cd21624c ("wifi: mt76: mt7996: add driver for MediaTek Wi-Fi 7 (802.11be) devices")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://patch.msgid.link/20260226-mt76-addba-req-oob-access-v1-1-b0f6d1ad4850@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/mac.c b/drivers/net/wireless/mediatek/mt76/mt7996/mac.c
index 2560e2f46e89a4bc46e21d796fca80b7decefa5c..d4f3ee943b4727a0e20f96a55db3bf055df20cc7 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7996/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7996/mac.c
@@ -800,6 +800,7 @@ mt7996_mac_write_txwi_80211(struct mt7996_dev *dev, __le32 *txwi,
        u32 val;
 
        if (ieee80211_is_action(fc) &&
+           skb->len >= IEEE80211_MIN_ACTION_SIZE + 1 &&
            mgmt->u.action.category == WLAN_CATEGORY_BACK &&
            mgmt->u.action.u.addba_req.action_code == WLAN_ACTION_ADDBA_REQ) {
                if (is_mt7990(&dev->mt76))