[ 033/187] be2net: fix a race in be_xmit()

Greg Kroah-Hartman
2012-07-12T23:45:07Z

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit cd8f76c0a0c6fce0b2cf23c9bd0123f91453f46d ]

As soon as hardware is notified of a transmit, we no longer can assume
skb can be dereferenced, as TX completion might have freed the packet.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/emulex/benet/be_main.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -731,6 +731,8 @@ static netdev_tx_t be_xmit(struct sk_buf

copied = make_tx_wrbs(adapter, txq, skb, wrb_cnt, dummy_wrb);
if (copied) {
+ int gso_segs = skb_shinfo(skb)->gso_segs;
+
/* record the sent skb in the sent_skb table */
BUG_ON(txo->sent_skb_list[start]);
txo->sent_skb_list[start] = skb;
@@ -748,8 +750,7 @@ static netdev_tx_t be_xmit(struct sk_buf

be_txq_notify(adapter, txq->id, wrb_cnt);

- be_tx_stats_update(txo, wrb_cnt, copied,
- skb_shinfo(skb)->gso_segs, stopped);
+ be_tx_stats_update(txo, wrb_cnt, copied, gso_segs, stopped);
} else {
txq->head = start;
dev_kfree_skb_any(skb);