sch_sfq: add sanity check for the packet length

The packet length should be checked before the packet data is dereferenced.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Changli Gao 2010-08-04 04:58:59 +00:00 committed by David S. Miller
parent 12dc96d167
commit f2f009812f

View file

@ -122,7 +122,11 @@ static unsigned sfq_hash(struct sfq_sched_data *q, struct sk_buff *skb)
switch (skb->protocol) {
case htons(ETH_P_IP):
{
const struct iphdr *iph = ip_hdr(skb);
const struct iphdr *iph;
if (!pskb_network_may_pull(skb, sizeof(*iph)))
goto err;
iph = ip_hdr(skb);
h = (__force u32)iph->daddr;
h2 = (__force u32)iph->saddr ^ iph->protocol;
if (!(iph->frag_off&htons(IP_MF|IP_OFFSET)) &&
@ -131,25 +135,32 @@ static unsigned sfq_hash(struct sfq_sched_data *q, struct sk_buff *skb)
iph->protocol == IPPROTO_UDPLITE ||
iph->protocol == IPPROTO_SCTP ||
iph->protocol == IPPROTO_DCCP ||
iph->protocol == IPPROTO_ESP))
iph->protocol == IPPROTO_ESP) &&
pskb_network_may_pull(skb, iph->ihl * 4 + 4))
h2 ^= *(((u32*)iph) + iph->ihl);
break;
}
case htons(ETH_P_IPV6):
{
struct ipv6hdr *iph = ipv6_hdr(skb);
struct ipv6hdr *iph;
if (!pskb_network_may_pull(skb, sizeof(*iph)))
goto err;
iph = ipv6_hdr(skb);
h = (__force u32)iph->daddr.s6_addr32[3];
h2 = (__force u32)iph->saddr.s6_addr32[3] ^ iph->nexthdr;
if (iph->nexthdr == IPPROTO_TCP ||
iph->nexthdr == IPPROTO_UDP ||
iph->nexthdr == IPPROTO_UDPLITE ||
iph->nexthdr == IPPROTO_SCTP ||
iph->nexthdr == IPPROTO_DCCP ||
iph->nexthdr == IPPROTO_ESP)
if ((iph->nexthdr == IPPROTO_TCP ||
iph->nexthdr == IPPROTO_UDP ||
iph->nexthdr == IPPROTO_UDPLITE ||
iph->nexthdr == IPPROTO_SCTP ||
iph->nexthdr == IPPROTO_DCCP ||
iph->nexthdr == IPPROTO_ESP) &&
pskb_network_may_pull(skb, sizeof(*iph) + 4))
h2 ^= *(u32*)&iph[1];
break;
}
default:
err:
h = (unsigned long)skb_dst(skb) ^ (__force u32)skb->protocol;
h2 = (unsigned long)skb->sk;
}