releases/4.15.17/vti6-better-validate-user-provided-tunnel-names.patch

   1 From foo@baz Tue Apr 10 23:19:36 CEST 2018
   2 From: Eric Dumazet <edumazet@google.com>
   3 Date: Thu, 5 Apr 2018 06:39:31 -0700
   4 Subject: vti6: better validate user provided tunnel names
   5
   6 From: Eric Dumazet <edumazet@google.com>
   7
   8
   9 [ Upstream commit 537b361fbcbcc3cd6fe2bb47069fd292b9256d16 ]
  10
  11 Use valid_name() to make sure user does not provide illegal
  12 device name.
  13
  14 Fixes: ed1efb2aefbb ("ipv6: Add support for IPsec virtual tunnel interfaces")
  15 Signed-off-by: Eric Dumazet <edumazet@google.com>
  16 Cc: Steffen Klassert <steffen.klassert@secunet.com>
  17 Signed-off-by: David S. Miller <davem@davemloft.net>
  18 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  19 ---
  20  net/ipv6/ip6_vti.c |    7 +++++--
  21  1 file changed, 5 insertions(+), 2 deletions(-)
  22
  23 --- a/net/ipv6/ip6_vti.c
  24 +++ b/net/ipv6/ip6_vti.c
  25 @@ -212,10 +212,13 @@ static struct ip6_tnl *vti6_tnl_create(s
  26         char name[IFNAMSIZ];
  27         int err;
  28
  29 -       if (p->name[0])
  30 +       if (p->name[0]) {
  31 +               if (!dev_valid_name(p->name))
  32 +                       goto failed;
  33                 strlcpy(name, p->name, IFNAMSIZ);
  34 -       else
  35 +       } else {
  36                 sprintf(name, "ip6_vti%%d");
  37 +       }
  38
  39         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup);
  40         if (!dev)