From 2bb9966c233293c9959f4d77a3c994182604472e Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 24 May 2012 14:32:20 +0200 Subject: [PATCH] ath9k: fix a use-after-free-bug when ath_tx_setup_buffer() fails commit 81357a281dcc454841532c46b30e6f2ba12b73ea upstream. ath_tx_setup_buffer() can fail if there is no ath_buf left, or if mapping DMA failed. In this case it frees the skb passed to it. If ath_tx_setup_buffer is called from ath_tx_form_aggr, the skb is still linked into the tid buffer list and must be dequeued before being released. Signed-off-by: Felix Fietkau Signed-off-by: John W. Linville Signed-off-by: Ben Hutchings --- drivers/net/wireless/ath/ath9k/xmit.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index 03b0a651a591..76fd2774d810 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -64,7 +64,8 @@ static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid, static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc, struct ath_txq *txq, struct ath_atx_tid *tid, - struct sk_buff *skb); + struct sk_buff *skb, + bool dequeue); enum { MCS_HT20, @@ -761,7 +762,7 @@ static enum ATH_AGGR_STATUS ath_tx_form_aggr(struct ath_softc *sc, fi = get_frame_info(skb); bf = fi->bf; if (!fi->bf) - bf = ath_tx_setup_buffer(sc, txq, tid, skb); + bf = ath_tx_setup_buffer(sc, txq, tid, skb, true); if (!bf) continue; @@ -1669,7 +1670,7 @@ static void ath_tx_send_ampdu(struct ath_softc *sc, struct ath_atx_tid *tid, return; } - bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb); + bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb, false); if (!bf) return; @@ -1696,7 +1697,7 @@ static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq, bf = fi->bf; if (!bf) - bf = ath_tx_setup_buffer(sc, txq, tid, skb); + bf = ath_tx_setup_buffer(sc, txq, tid, skb, false); if (!bf) return; @@ -1761,7 +1762,8 @@ u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate) static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc, struct ath_txq *txq, struct ath_atx_tid *tid, - struct sk_buff *skb) + struct sk_buff *skb, + bool dequeue) { struct ath_common *common = ath9k_hw_common(sc->sc_ah); struct ath_frame_info *fi = get_frame_info(skb); @@ -1802,6 +1804,8 @@ static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc, return bf; error: + if (dequeue) + __skb_unlink(skb, &tid->buf_q); dev_kfree_skb_any(skb); return NULL; } @@ -1833,7 +1837,7 @@ static void ath_tx_start_dma(struct ath_softc *sc, struct sk_buff *skb, */ ath_tx_send_ampdu(sc, tid, skb, txctl); } else { - bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb); + bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb, false); if (!bf) goto out; -- 2.39.2