Re: [PATCH] Add missing skb->dev assignment in Frame Relay RX code

From: Stephen Hemminger
Date: Sun Jun 29 2008 - 16:04:45 EST


On Sun, 29 Jun 2008 21:48:11 +0200
Krzysztof Halasa <khc@xxxxxxxxx> wrote:

> Hi,
>
> Commit 4c13eb6657fe9ef7b4dc8f1a405c902e9e5234e0 ([ETH]: Make
> eth_type_trans set skb->dev like the other *_type_trans) removed
> skb->dev assignment from hdlc_fr.c:fr_rx(). Unfortunately it was also
> needed for cases other than eth_type_trans().
>
> Adding it back.
>
> It's quite serious and may be a security risk as it causes a wrong
> input interface indication (the physical hdlcX instead of logical
> pvcX). Probably -stable class fix.
>
> Signed-off-by: Krzysztof Halasa <khc@xxxxxxxxx>
>
> diff --git a/drivers/net/wan/hdlc_fr.c b/drivers/net/wan/hdlc_fr.c
> index c4ab032..3a86e64 100644
> --- a/drivers/net/wan/hdlc_fr.c
> +++ b/drivers/net/wan/hdlc_fr.c
> @@ -1008,6 +1008,7 @@ static int fr_rx(struct sk_buff *skb)
> stats->rx_bytes += skb->len;
> if (pvc->state.becn)
> stats->rx_compressed++;
> + skb->dev = dev;
> netif_rx(skb);
> return NET_RX_SUCCESS;
> } else {
> --
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Better to use netdev_alloc_skb for receive buffers instead.
--- a/drivers/net/wan/hdlc_fr.c 2008-06-29 13:02:42.000000000 -0700
+++ b/drivers/net/wan/hdlc_fr.c 2008-06-29 13:04:01.000000000 -0700
@@ -515,7 +515,7 @@ static void fr_lmi_send(struct net_devic
}
}

- skb = dev_alloc_skb(len);
+ skb = netdev_alloc_skb(dev, len);
if (!skb) {
printk(KERN_WARNING "%s: Memory squeeze on fr_lmi_send()\n",
dev->name);
--
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