b1879204dd
Also removes redundant skb->len < x check which can't be true once pskb_may_pull(skb, x) succeeded. $ diff-funcs pim_rcv ipmr.c ipmr.c pim_rcv_v1 --- ipmr.c:pim_rcv() +++ ipmr.c:pim_rcv_v1() @@ -1,22 +1,27 @@ -static int pim_rcv(struct sk_buff * skb) +int pim_rcv_v1(struct sk_buff * skb) { - struct pimreghdr *pim; + struct igmphdr *pim; struct iphdr *encap; struct net_device *reg_dev = NULL; if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap))) goto drop; - pim = (struct pimreghdr *)skb_transport_header(skb); - if (pim->type != ((PIM_VERSION<<4)|(PIM_REGISTER)) || - (pim->flags&PIM_NULL_REGISTER) || - (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 && - csum_fold(skb_checksum(skb, 0, skb->len, 0)))) + pim = igmp_hdr(skb); + + if (!mroute_do_pim || + skb->len < sizeof(*pim) + sizeof(*encap) || + pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER) goto drop; - /* check if the inner packet is destined to mcast group */ encap = (struct iphdr *)(skb_transport_header(skb) + - sizeof(struct pimreghdr)); + sizeof(struct igmphdr)); + /* + Check that: + a. packet is really destinted to a multicast group + b. packet is not a NULL-REGISTER + c. packet is not truncated + */ if (!ipv4_is_multicast(encap->daddr) || encap->tot_len == 0 || ntohs(encap->tot_len) + sizeof(*pim) > skb->len) @@ -40,9 +45,9 @@ skb->ip_summed = 0; skb->pkt_type = PACKET_HOST; dst_release(skb->dst); + skb->dst = NULL; reg_dev->stats.rx_bytes += skb->len; reg_dev->stats.rx_packets++; - skb->dst = NULL; nf_reset(skb); netif_rx(skb); dev_put(reg_dev); $ codiff net/ipv4/ipmr.o.old net/ipv4/ipmr.o.new net/ipv4/ipmr.c: pim_rcv_v1 | -283 pim_rcv | -284 2 functions changed, 567 bytes removed net/ipv4/ipmr.c: __pim_rcv | +307 1 function changed, 307 bytes added net/ipv4/ipmr.o.new: 3 functions changed, 307 bytes added, 567 bytes removed, diff: -260 (Tested on x86_64). It seems that pimlen arg could be left out as well and eq-sizedness of structs trapped with BUILD_BUG_ON but I don't think that's more than a cosmetic flaw since there aren't that many args anyway. Compile tested. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net> |
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.. | ||
netfilter | ||
af_inet.c | ||
ah4.c | ||
arp.c | ||
cipso_ipv4.c | ||
datagram.c | ||
devinet.c | ||
esp4.c | ||
fib_frontend.c | ||
fib_hash.c | ||
fib_lookup.h | ||
fib_rules.c | ||
fib_semantics.c | ||
fib_trie.c | ||
icmp.c | ||
igmp.c | ||
inet_connection_sock.c | ||
inet_diag.c | ||
inet_fragment.c | ||
inet_hashtables.c | ||
inet_lro.c | ||
inet_timewait_sock.c | ||
inetpeer.c | ||
ip_forward.c | ||
ip_fragment.c | ||
ip_gre.c | ||
ip_input.c | ||
ip_options.c | ||
ip_output.c | ||
ip_sockglue.c | ||
ipcomp.c | ||
ipconfig.c | ||
ipip.c | ||
ipmr.c | ||
Kconfig | ||
Makefile | ||
netfilter.c | ||
proc.c | ||
protocol.c | ||
raw.c | ||
route.c | ||
syncookies.c | ||
sysctl_net_ipv4.c | ||
tcp_bic.c | ||
tcp_cong.c | ||
tcp_cubic.c | ||
tcp_diag.c | ||
tcp_highspeed.c | ||
tcp_htcp.c | ||
tcp_hybla.c | ||
tcp_illinois.c | ||
tcp_input.c | ||
tcp_ipv4.c | ||
tcp_lp.c | ||
tcp_minisocks.c | ||
tcp_output.c | ||
tcp_probe.c | ||
tcp_scalable.c | ||
tcp_timer.c | ||
tcp_vegas.c | ||
tcp_vegas.h | ||
tcp_veno.c | ||
tcp_westwood.c | ||
tcp_yeah.c | ||
tcp.c | ||
tunnel4.c | ||
udp_impl.h | ||
udp.c | ||
udplite.c | ||
xfrm4_input.c | ||
xfrm4_mode_beet.c | ||
xfrm4_mode_transport.c | ||
xfrm4_mode_tunnel.c | ||
xfrm4_output.c | ||
xfrm4_policy.c | ||
xfrm4_state.c | ||
xfrm4_tunnel.c |