From: Jouni Malinen jouni@codeaurora.org
stable inclusion from linux-4.19.205 commit 08c613a2cb06c68ef4e7733e052af067b21e5dbb CVE: CVE-2020-3702
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commit ca2848022c12789685d3fab3227df02b863f9696 upstream.
Do not delete a key cache entry that is still being referenced by pending frames in TXQs. This avoids reuse of the key cache entry while a frame might still be transmitted using it.
To avoid having to do any additional operations during the main TX path operations, track pending key cache entries in a new bitmap and check whether any pending entries can be deleted before every new key add/remove operation. Also clear any remaining entries when stopping the interface.
Signed-off-by: Jouni Malinen jouni@codeaurora.org Signed-off-by: Kalle Valo kvalo@codeaurora.org Link: https://lore.kernel.org/r/20201214172118.18100-6-jouni@codeaurora.org Cc: Pali Rohár pali@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com Reviewed-by: Xiu Jianfeng xiujianfeng@huawei.com Reviewed-by: Yue Haibing yuehaibing@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/net/wireless/ath/ath9k/hw.h | 1 + drivers/net/wireless/ath/ath9k/main.c | 87 ++++++++++++++++++++++++++- 2 files changed, 87 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h index 68956cdc8c9ae..4b5687b6c0c9a 100644 --- a/drivers/net/wireless/ath/ath9k/hw.h +++ b/drivers/net/wireless/ath/ath9k/hw.h @@ -818,6 +818,7 @@ struct ath_hw { struct ath9k_pacal_info pacal_info; struct ar5416Stats stats; struct ath9k_tx_queue_info txq[ATH9K_NUM_TX_QUEUES]; + DECLARE_BITMAP(pending_del_keymap, ATH_KEYMAX);
enum ath9k_int imask; u32 imrs2_reg; diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c index bf428e4d409f9..577f5f79b44b8 100644 --- a/drivers/net/wireless/ath/ath9k/main.c +++ b/drivers/net/wireless/ath/ath9k/main.c @@ -818,12 +818,80 @@ static void ath9k_tx(struct ieee80211_hw *hw, ieee80211_free_txskb(hw, skb); }
+static bool ath9k_txq_list_has_key(struct list_head *txq_list, u32 keyix) +{ + struct ath_buf *bf; + struct ieee80211_tx_info *txinfo; + struct ath_frame_info *fi; + + list_for_each_entry(bf, txq_list, list) { + if (bf->bf_state.stale || !bf->bf_mpdu) + continue; + + txinfo = IEEE80211_SKB_CB(bf->bf_mpdu); + fi = (struct ath_frame_info *)&txinfo->rate_driver_data[0]; + if (fi->keyix == keyix) + return true; + } + + return false; +} + +static bool ath9k_txq_has_key(struct ath_softc *sc, u32 keyix) +{ + struct ath_hw *ah = sc->sc_ah; + int i; + struct ath_txq *txq; + bool key_in_use = false; + + for (i = 0; !key_in_use && i < ATH9K_NUM_TX_QUEUES; i++) { + if (!ATH_TXQ_SETUP(sc, i)) + continue; + txq = &sc->tx.txq[i]; + if (!txq->axq_depth) + continue; + if (!ath9k_hw_numtxpending(ah, txq->axq_qnum)) + continue; + + ath_txq_lock(sc, txq); + key_in_use = ath9k_txq_list_has_key(&txq->axq_q, keyix); + if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) { + int idx = txq->txq_tailidx; + + while (!key_in_use && + !list_empty(&txq->txq_fifo[idx])) { + key_in_use = ath9k_txq_list_has_key( + &txq->txq_fifo[idx], keyix); + INCR(idx, ATH_TXFIFO_DEPTH); + } + } + ath_txq_unlock(sc, txq); + } + + return key_in_use; +} + +static void ath9k_pending_key_del(struct ath_softc *sc, u8 keyix) +{ + struct ath_hw *ah = sc->sc_ah; + struct ath_common *common = ath9k_hw_common(ah); + + if (!test_bit(keyix, ah->pending_del_keymap) || + ath9k_txq_has_key(sc, keyix)) + return; + + /* No more TXQ frames point to this key cache entry, so delete it. */ + clear_bit(keyix, ah->pending_del_keymap); + ath_key_delete(common, keyix); +} + static void ath9k_stop(struct ieee80211_hw *hw) { struct ath_softc *sc = hw->priv; struct ath_hw *ah = sc->sc_ah; struct ath_common *common = ath9k_hw_common(ah); bool prev_idle; + int i;
ath9k_deinit_channel_context(sc);
@@ -891,6 +959,9 @@ static void ath9k_stop(struct ieee80211_hw *hw)
spin_unlock_bh(&sc->sc_pcu_lock);
+ for (i = 0; i < ATH_KEYMAX; i++) + ath9k_pending_key_del(sc, i); + /* Clear key cache entries explicitly to get rid of any potentially * remaining keys. */ @@ -1704,6 +1775,12 @@ static int ath9k_set_key(struct ieee80211_hw *hw, if (sta) an = (struct ath_node *)sta->drv_priv;
+ /* Delete pending key cache entries if no more frames are pointing to + * them in TXQs. + */ + for (i = 0; i < ATH_KEYMAX; i++) + ath9k_pending_key_del(sc, i); + switch (cmd) { case SET_KEY: if (sta) @@ -1733,7 +1810,15 @@ static int ath9k_set_key(struct ieee80211_hw *hw, } break; case DISABLE_KEY: - ath_key_delete(common, key->hw_key_idx); + if (ath9k_txq_has_key(sc, key->hw_key_idx)) { + /* Delay key cache entry deletion until there are no + * remaining TXQ frames pointing to this entry. + */ + set_bit(key->hw_key_idx, sc->sc_ah->pending_del_keymap); + ath_hw_keysetmac(common, key->hw_key_idx, NULL); + } else { + ath_key_delete(common, key->hw_key_idx); + } if (an) { for (i = 0; i < ARRAY_SIZE(an->key_idx); i++) { if (an->key_idx[i] != key->hw_key_idx)