ath9k: fix a use-after-free-bug when ath_tx_setup_buffer() fails
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 <nbd@openwrt.org>
Cc: stable@vger.kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 23eaa1b..d59dd01 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -64,7 +64,8 @@
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,
@@ -811,7 +812,7 @@
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;
@@ -1726,7 +1727,7 @@
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;
@@ -1753,7 +1754,7 @@
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;
@@ -1814,7 +1815,8 @@
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);
@@ -1863,6 +1865,8 @@
return bf;
error:
+ if (dequeue)
+ __skb_unlink(skb, &tid->buf_q);
dev_kfree_skb_any(skb);
return NULL;
}
@@ -1893,7 +1897,7 @@
*/
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)
return;