Commit 37ec274e authored Dec 19, 2013 by Eric Dumazet Committed by David S. Miller Dec 27, 2013

arc_emac: fix potential use after free



Signed-off-by: Eric Dumazet <edumazet@google.com>

skb_tx_timestamp(skb) should be called _before_ TX completion
has a chance to trigger, otherwise it is too late and we access
freed memory.

Fixes: e4f2379d ("ethernet/arc/arc_emac - Add new driver")
From: Eric Dumazet <edumazet@google.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 37567910

drivers/net/ethernet/arc/emac_main.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -565,6 +565,8 @@ static int arc_emac_tx(struct sk_buff skb, struct net_device ndev)
		/* Make sure pointer to data buffer is set */
		wmb();

		skb_tx_timestamp(skb);

		*info = cpu_to_le32(FOR_EMAC \| FIRST_OR_LAST_MASK \| len);

		/* Increment index to point to the next BD */
		@@ -579,8 +581,6 @@ static int arc_emac_tx(struct sk_buff skb, struct net_device ndev)

		arc_reg_set(priv, R_STATUS, TXPL_MASK);

		skb_tx_timestamp(skb);

		return NETDEV_TX_OK;
		}