From ab43ed8b7490cb387782423ecf74aeee7237e591 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 22 Sep 2012 00:08:29 +0000 Subject: [PATCH] ipv4: raw: fix icmp_filter() icmp_filter() should not modify its input, or else its caller would need to recompute ip_hdr() if skb->head is reallocated. Use skb_header_pointer() instead of pskb_may_pull() and change the prototype to make clear both sk and skb are const. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/raw.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index ff0f071969ea..d23c6571ba1c 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -131,18 +131,20 @@ static struct sock *__raw_v4_lookup(struct net *net, struct sock *sk, * 0 - deliver * 1 - block */ -static __inline__ int icmp_filter(struct sock *sk, struct sk_buff *skb) +static int icmp_filter(const struct sock *sk, const struct sk_buff *skb) { - int type; + struct icmphdr _hdr; + const struct icmphdr *hdr; - if (!pskb_may_pull(skb, sizeof(struct icmphdr))) + hdr = skb_header_pointer(skb, skb_transport_offset(skb), + sizeof(_hdr), &_hdr); + if (!hdr) return 1; - type = icmp_hdr(skb)->type; - if (type < 32) { + if (hdr->type < 32) { __u32 data = raw_sk(sk)->filter.data; - return ((1 << type) & data) != 0; + return ((1U << hdr->type) & data) != 0; } /* Do not block unknown ICMP types */ -- GitLab