patches/kernel/0012-net-udp-fix-SO_BINDTODEVICE.patch

   1 From patchwork Wed May  9 10:42:34 2018
   2 Content-Type: text/plain; charset="utf-8"
   3 MIME-Version: 1.0
   4 Content-Transfer-Encoding: 7bit
   5 Subject: [net] udp: fix SO_BINDTODEVICE
   6 X-Patchwork-Submitter: Paolo Abeni <pabeni@redhat.com>
   7 X-Patchwork-Id: 910747
   8 X-Patchwork-Delegate: davem@davemloft.net
   9 Message-Id: <9445dd5d149af16463df4d0502b2667ee2b6f4e8.1525862461.git.pabeni@redhat.com>
  10 To: netdev@vger.kernel.org
  11 Cc: Damir Mansurov <dnman@oktetlabs.ru>, David Ahern <dsahern@gmail.com>,
  12  David Miller <davem@davemloft.net>
  13 Date: Wed,  9 May 2018 12:42:34 +0200
  14 From: Paolo Abeni <pabeni@redhat.com>
  15 List-Id: <netdev.vger.kernel.org>
  16
  17 Damir reported a breakage of SO_BINDTODEVICE for UDP sockets.
  18 In absence of VRF devices, after commit fb74c27735f0 ("net:
  19 ipv4: add second dif to udp socket lookups") the dif mismatch
  20 isn't fatal anymore for UDP socket lookup with non null
  21 sk_bound_dev_if, breaking SO_BINDTODEVICE semantics.
  22
  23 This changeset addresses the issue making the dif match mandatory
  24 again in the above scenario.
  25
  26 Reported-by: Damir Mansurov <dnman@oktetlabs.ru>
  27 Fixes: fb74c27735f0 ("net: ipv4: add second dif to udp socket lookups")
  28 Fixes: 1801b570dd2a ("net: ipv6: add second dif to udp socket lookups")
  29 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
  30 Acked-by: David Ahern <dsahern@gmail.com>
  31 ---
  32  net/ipv4/udp.c | 4 ++--
  33  net/ipv6/udp.c | 4 ++--
  34  2 files changed, 4 insertions(+), 4 deletions(-)
  35
  36 diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
  37 index 24b5c59b1c53..c2a292dfd137 100644
  38 --- a/net/ipv4/udp.c
  39 +++ b/net/ipv4/udp.c
  40 @@ -401,9 +401,9 @@ static int compute_score(struct sock *sk, struct net *net,
  41                 bool dev_match = (sk->sk_bound_dev_if == dif ||
  42                                   sk->sk_bound_dev_if == sdif);
  43
  44 -               if (exact_dif && !dev_match)
  45 +               if (!dev_match)
  46                         return -1;
  47 -               if (sk->sk_bound_dev_if && dev_match)
  48 +               if (sk->sk_bound_dev_if)
  49                         score += 4;
  50         }
  51
  52 diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
  53 index 4ec76a87aeb8..ea0730028e5d 100644
  54 --- a/net/ipv6/udp.c
  55 +++ b/net/ipv6/udp.c
  56 @@ -148,9 +148,9 @@ static int compute_score(struct sock *sk, struct net *net,
  57                 bool dev_match = (sk->sk_bound_dev_if == dif ||
  58                                   sk->sk_bound_dev_if == sdif);
  59
  60 -               if (exact_dif && !dev_match)
  61 +               if (!dev_match)
  62                         return -1;
  63 -               if (sk->sk_bound_dev_if && dev_match)
  64 +               if (sk->sk_bound_dev_if)
  65                         score++;
  66         }
  67