From: Eric Dumazet Date: Sat, 22 Sep 2012 00:08:29 +0000 (+0000) Subject: ipv4: raw: fix icmp_filter() X-Git-Tag: firefly_0821_release~7541^2~536 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a1b995a2f5c69ae3088b153ed5d095561ded6eb4;p=firefly-linux-kernel-4.4.55.git ipv4: raw: fix icmp_filter() [ Upstream commit ab43ed8b7490cb387782423ecf74aeee7237e591 ] 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index c9893d43242e..3d8bb189babb 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -130,18 +130,20 @@ found: * 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 */