Commit 1c9b7aa1 authored Jan 09, 2008 by Herbert Xu Committed by David S. Miller Jan 09, 2008

[ATM]: Check IP header validity in mpc_send_packet



Al went through the ip_fast_csum callers and found this piece of code
that did not validate the IP header.  While root crashing the machine
by sending bogus packets through raw or AF_PACKET sockets isn't that
serious, it is still nice to react gracefully.

This patch ensures that the skb has enough data for an IP header and
that the header length field is valid.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 1ac4f008

net/atm/mpc.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -542,6 +542,13 @@ static int mpc_send_packet(struct sk_buff skb, struct net_device dev)
		if (eth->h_proto != htons(ETH_P_IP))
		goto non_ip; /* Multi-Protocol Over ATM :-) */

		/* Weed out funny packets (e.g., AF_PACKET or raw). */
		if (skb->len < ETH_HLEN + sizeof(struct iphdr))
		goto non_ip;
		skb_set_network_header(skb, ETH_HLEN);
		if (skb->len < ETH_HLEN + ip_hdr(skb)->ihl * 4 \|\| ip_hdr(skb)->ihl < 5)
		goto non_ip;

		while (i < mpc->number_of_mps_macs) {
		if (!compare_ether_addr(eth->h_dest, (mpc->mps_macs + i*ETH_ALEN)))
		if ( send_via_shortcut(skb, mpc) == 0 ) /* try shortcut */

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