pppoe: Unshare skb before anything else

We need to unshare the skb first as otherwise pskb_may_pull may
write to a shared skb which could be bad.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Herbert Xu 2008-06-10 14:08:25 -07:00 committed by David S. Miller
parent 392fdb0e35
commit bc6cffd177

View File

@ -432,12 +432,12 @@ static int pppoe_disc_rcv(struct sk_buff *skb,
if (dev_net(dev) != &init_net)
goto abort;
if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
goto abort;
if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
goto out;
if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
goto abort;
ph = pppoe_hdr(skb);
if (ph->code != PADT_CODE)
goto abort;