| Message ID | 1433176465-22941-1-git-send-email-shawn.bohrer@gmail.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
Hello. On 06/01/2015 07:34 PM, Shawn Bohrer wrote: > From: Shawn Bohrer <sbohrer@rgmadvisors.com> > 421b3885bf6d56391297844f43fb7154a6396e12 "udp: ipv4: Add udp early > demux" introduced a regression that allowed sockets bound to INADDR_ANY > to receive packets from multicast groups that the socket had not joined. > For example a socket that had joined 224.168.2.9 could also receive > packets from 225.168.2.9 despite not having joined that group if > ip_early_demux is enabled. > Fix this by calling ip_check_mc_rcu() in udp_v4_early_demux() to verify > that the multicast packet is indeed ours. > Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com> > Reported-by: Yurij M. Plotnikov <Yurij.Plotnikov@oktetlabs.ru> > --- > net/ipv4/udp.c | 18 +++++++++++++----- > 1 file changed, 13 insertions(+), 5 deletions(-) > diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c > index d10b7e0..17d31f5 100644 > --- a/net/ipv4/udp.c > +++ b/net/ipv4/udp.c [...] > @@ -1971,10 +1972,17 @@ void udp_v4_early_demux(struct sk_buff *skb) > uh = udp_hdr(skb); > > if (skb->pkt_type == PACKET_BROADCAST || > - skb->pkt_type == PACKET_MULTICAST) > - sk = __udp4_lib_mcast_demux_lookup(net, uh->dest, iph->daddr, > - uh->source, iph->saddr, dif); > - else if (skb->pkt_type == PACKET_HOST) > + skb->pkt_type == PACKET_MULTICAST) { > + struct in_device *in_dev = __in_dev_get_rcu(skb->dev); > + > + if (in_dev) { > + int our = ip_check_mc_rcu(in_dev, iph->daddr, iph->saddr, > + iph->protocol); > + if (our) > + sk = __udp4_lib_mcast_demux_lookup(net, uh->dest, iph->daddr, > + uh->source, iph->saddr, dif); > + } > + } else if (skb->pkt_type == PACKET_HOST) > sk = __udp4_lib_demux_lookup(net, uh->dest, iph->daddr, > uh->source, iph->saddr, dif); > else Must add {} around all branches of the *if* statement if you're adding them around just one; see Documentation/CodingStyle. WBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index d10b7e0..17d31f5 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -90,6 +90,7 @@ #include <linux/socket.h> #include <linux/sockios.h> #include <linux/igmp.h> +#include <linux/inetdevice.h> #include <linux/in.h> #include <linux/errno.h> #include <linux/timer.h> @@ -1959,7 +1960,7 @@ void udp_v4_early_demux(struct sk_buff *skb) struct net *net = dev_net(skb->dev); const struct iphdr *iph; const struct udphdr *uh; - struct sock *sk; + struct sock *sk = NULL; struct dst_entry *dst; int dif = skb->dev->ifindex; @@ -1971,10 +1972,17 @@ void udp_v4_early_demux(struct sk_buff *skb) uh = udp_hdr(skb); if (skb->pkt_type == PACKET_BROADCAST || - skb->pkt_type == PACKET_MULTICAST) - sk = __udp4_lib_mcast_demux_lookup(net, uh->dest, iph->daddr, - uh->source, iph->saddr, dif); - else if (skb->pkt_type == PACKET_HOST) + skb->pkt_type == PACKET_MULTICAST) { + struct in_device *in_dev = __in_dev_get_rcu(skb->dev); + + if (in_dev) { + int our = ip_check_mc_rcu(in_dev, iph->daddr, iph->saddr, + iph->protocol); + if (our) + sk = __udp4_lib_mcast_demux_lookup(net, uh->dest, iph->daddr, + uh->source, iph->saddr, dif); + } + } else if (skb->pkt_type == PACKET_HOST) sk = __udp4_lib_demux_lookup(net, uh->dest, iph->daddr, uh->source, iph->saddr, dif); else