From 4fdec031b9169b3c17938b9c4168f099f457169c Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Fri, 12 Mar 2010 04:02:43 +0100 Subject: [PATCH] ath9k: fix BUG_ON triggered by PAE frames When I initially stumbled upon sequence number problems with PAE frames in ath9k, I submitted a patch to remove all special cases for PAE frames and let them go through the normal transmit path. Out of concern about crypto incompatibility issues, this change was merged instead: commit 6c8afef551fef87a3bf24f8a74c69a7f2f72fc82 Author: Sujith Date: Tue Feb 9 10:07:00 2010 +0530 ath9k: Fix sequence numbers for PAE frames After a lot of testing, I'm able to reliably trigger a driver crash on rekeying with current versions with this change in place. It seems that the driver does not support sending out regular MPDUs with the same TID while an A-MPDU session is active. This leads to duplicate entries in the TID Tx buffer, which hits the following BUG_ON in ath_tx_addto_baw(): index = ATH_BA_INDEX(tid->seq_start, bf->bf_seqno); cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1); BUG_ON(tid->tx_buf[cindex] != NULL); I believe until we actually have a reproducible case of an incompatibility with another AP using no PAE special cases, we should simply get rid of this mess. This patch completely fixes my crash issues in STA mode and makes it stay connected without throughput drops or connectivity issues even when the AP is configured to a very short group rekey interval. Signed-off-by: Felix Fietkau Cc: stable@kernel.org Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/xmit.c | 21 +-------------------- 1 file changed, 1 insertion(+), 20 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index b2c8207f7bc1..294b486bc3ed 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -1353,25 +1353,6 @@ static enum ath9k_pkt_type get_hw_packet_type(struct sk_buff *skb) return htype; } -static bool is_pae(struct sk_buff *skb) -{ - struct ieee80211_hdr *hdr; - __le16 fc; - - hdr = (struct ieee80211_hdr *)skb->data; - fc = hdr->frame_control; - - if (ieee80211_is_data(fc)) { - if (ieee80211_is_nullfunc(fc) || - /* Port Access Entity (IEEE 802.1X) */ - (skb->protocol == cpu_to_be16(ETH_P_PAE))) { - return true; - } - } - - return false; -} - static int get_hw_crypto_keytype(struct sk_buff *skb) { struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb); @@ -1696,7 +1677,7 @@ static void ath_tx_start_dma(struct ath_softc *sc, struct ath_buf *bf, goto tx_done; } - if ((tx_info->flags & IEEE80211_TX_CTL_AMPDU) && !is_pae(skb)) { + if (tx_info->flags & IEEE80211_TX_CTL_AMPDU) { /* * Try aggregation if it's a unicast data frame * and the destination is HT capable. -- 2.20.1