net: ll_temac: Fix bug causing buffer descriptor overrun
authorEsben Haabendal <esben@geanix.com>
Tue, 30 Apr 2019 07:17:56 +0000 (09:17 +0200)
committerDavid S. Miller <davem@davemloft.net>
Wed, 1 May 2019 18:33:30 +0000 (14:33 -0400)
As we are actually using a BD for both the skb and each frag contained in
it, the oldest TX BD would be overwritten when there was exactly one BD
less than needed.

Signed-off-by: Esben Haabendal <esben@geanix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/xilinx/ll_temac_main.c

index 7e42746f2292dc637331ec6fb7af7e339fe3eb33..68375655e61b745a0aa7d5d421aed02554125901 100644 (file)
@@ -743,7 +743,7 @@ temac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
        start_p = lp->tx_bd_p + sizeof(*lp->tx_bd_v) * lp->tx_bd_tail;
        cur_p = &lp->tx_bd_v[lp->tx_bd_tail];
 
-       if (temac_check_tx_bd_space(lp, num_frag)) {
+       if (temac_check_tx_bd_space(lp, num_frag + 1)) {
                if (!netif_queue_stopped(ndev))
                        netif_stop_queue(ndev);
                return NETDEV_TX_BUSY;