diff options
| author | Stephen Suryaputra <ssuryaextr@gmail.com> | 2019-06-26 02:21:16 -0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-06-26 12:40:10 -0700 |
| commit | 5b18f1289808fee5d04a7e6ecf200189f41a4db6 (patch) | |
| tree | c4f8ffda52e1fa30489d1eae8c7f4066c0fc2df6 /net/ipv4/ip_output.c | |
| parent | ee4297420d56a0033a8593e80b33fcc93fda8509 (diff) | |
ipv4: reset rt_iif for recirculated mcast/bcast out pkts
Multicast or broadcast egress packets have rt_iif set to the oif. These
packets might be recirculated back as input and lookup to the raw
sockets may fail because they are bound to the incoming interface
(skb_iif). If rt_iif is not zero, during the lookup, inet_iif() function
returns rt_iif instead of skb_iif. Hence, the lookup fails.
v2: Make it non vrf specific (David Ahern). Reword the changelog to
reflect it.
Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/ip_output.c')
| -rw-r--r-- | net/ipv4/ip_output.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 16f9159234a2..8c2ec35b6512 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -318,6 +318,7 @@ static int ip_finish_output(struct net *net, struct sock *sk, struct sk_buff *sk static int ip_mc_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb) { + struct rtable *new_rt; int ret; ret = BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb); @@ -326,6 +327,17 @@ static int ip_mc_finish_output(struct net *net, struct sock *sk, return ret; } + /* Reset rt_iif so that inet_iif() will return skb->skb_iif. Setting + * this to non-zero causes ipi_ifindex in in_pktinfo to be overwritten, + * see ipv4_pktinfo_prepare(). + */ + new_rt = rt_dst_clone(net->loopback_dev, skb_rtable(skb)); + if (new_rt) { + new_rt->rt_iif = 0; + skb_dst_drop(skb); + skb_dst_set(skb, &new_rt->dst); + } + return dev_loopback_xmit(net, sk, skb); } |