queue-3.18/dccp-do-not-use-ipv6-header-for-ipv4-flow.patch

   1 From foo@baz Thu Mar 28 23:25:55 CET 2019
   2 From: Eric Dumazet <edumazet@google.com>
   3 Date: Tue, 19 Mar 2019 05:46:18 -0700
   4 Subject: dccp: do not use ipv6 header for ipv4 flow
   5
   6 From: Eric Dumazet <edumazet@google.com>
   7
   8 [ Upstream commit e0aa67709f89d08c8d8e5bdd9e0b649df61d0090 ]
   9
  10 When a dual stack dccp listener accepts an ipv4 flow,
  11 it should not attempt to use an ipv6 header or
  12 inet6_iif() helper.
  13
  14 Fixes: 3df80d9320bc ("[DCCP]: Introduce DCCPv6")
  15 Signed-off-by: Eric Dumazet <edumazet@google.com>
  16 Signed-off-by: David S. Miller <davem@davemloft.net>
  17 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  18 ---
  19  net/dccp/ipv6.c |    4 ++--
  20  1 file changed, 2 insertions(+), 2 deletions(-)
  21
  22 --- a/net/dccp/ipv6.c
  23 +++ b/net/dccp/ipv6.c
  24 @@ -490,8 +490,8 @@ static struct sock *dccp_v6_request_recv
  25                 newnp->ipv6_mc_list = NULL;
  26                 newnp->ipv6_ac_list = NULL;
  27                 newnp->ipv6_fl_list = NULL;
  28 -               newnp->mcast_oif   = inet6_iif(skb);
  29 -               newnp->mcast_hops  = ipv6_hdr(skb)->hop_limit;
  30 +               newnp->mcast_oif   = inet_iif(skb);
  31 +               newnp->mcast_hops  = ip_hdr(skb)->ttl;
  32
  33                 /*
  34                  * No need to charge this sock to the relevant IPv6 refcnt debug socks count