diff options
| author | Changli Gao <xiaosuo@gmail.com> | 2010-08-04 04:58:59 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-08-04 21:53:16 -0700 |
| commit | f2f009812f1fdcaf40fa547282c1b90d3b702a7d (patch) | |
| tree | d6738a7481f2ee97cabfa44859a084d957d421c3 | |
| parent | 12dc96d1673feabef98eed1b5ff37abaa67fbe64 (diff) | |
| download | linux-f2f009812f1fdcaf40fa547282c1b90d3b702a7d.tar.bz2 | |
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>
| -rw-r--r-- | net/sched/sch_sfq.c | 29 |
1 files changed, 20 insertions, 9 deletions
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index c65762823f5e..e85352b5c88d 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -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; } |