On 5/20/19 2:40 AM, Mike Manning wrote:
> Since the commit 1893ff20275b ("net/ipv6: Add l3mdev check to
> ipv6_chk_addr_and_flags"), traceroute using TCP SYN or ICMP ECHO option
> and ping fail when specifying a source address typically on a loopback
> /dummy interface in the same VRF, e.g.:
>
> # ip vrf exec vrfgreen ping 3000::1 -I 2222::2
> ping: bind icmp socket: Cannot assign requested address
> # ip vrf exec vrfgreen traceroute 3000::1 -s 2222::2 -T
> bind: Cannot assign requested address
>
> IPv6 traceroute using default UDP and IPv4 ping & traceroute continue
> to work inside a VRF using a source address.
>
> The reason is that the source address is provided via bind without a
> device given by these applications in this case. The call to
> ipv6_check_addr() in rawv6_bind() returns false as the default VRF is
> assumed if no dev was given, but the src addr is in a non-default VRF.
>
> The solution is to check that the address exists in the L3 domain that
> the dev is part of only if the dev has been specified.
>
> Signed-off-by: Mike Manning <mmann...@vyatta.att-mail.com>
> ---
> net/ipv6/addrconf.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
> index f96d1de79509..3963306ec27f 100644
> --- a/net/ipv6/addrconf.c
> +++ b/net/ipv6/addrconf.c
> @@ -1908,6 +1908,7 @@ int ipv6_chk_addr_and_flags(struct net *net, const
> struct in6_addr *addr,
> int strict, u32 banned_flags)
> {
> unsigned int hash = inet6_addr_hash(net, addr);
> + const struct net_device *orig_dev = dev;
> const struct net_device *l3mdev;
> struct inet6_ifaddr *ifp;
> u32 ifp_flags;
> @@ -1922,7 +1923,7 @@ int ipv6_chk_addr_and_flags(struct net *net, const
> struct in6_addr *addr,
> if (!net_eq(dev_net(ifp->idev->dev), net))
> continue;
>
> - if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
> + if (orig_dev && l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
> continue;
>
> /* Decouple optimistic from tentative for evaluation here.
>
Wrong fix. When looking up the address you have to give the L3 domain of
interest.
This change:
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 84dbe21b71e5..96a3559f2a09 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -287,7 +287,9 @@ static int rawv6_bind(struct sock *sk, struct
sockaddr *uaddr, int addr_len)
/* Binding to link-local address requires an
interface */
if (!sk->sk_bound_dev_if)
goto out_unlock;
+ }
+ if (sk->sk_bound_dev_if) {
err = -ENODEV;
dev = dev_get_by_index_rcu(sock_net(sk),
sk->sk_bound_dev_if);
make raw binds similar to tcp. See:
c5ee066333ebc ("ipv6: Consider sk_bound_dev_if when binding a socket to
an address")
ec90ad334986f ("ipv6: Consider sk_bound_dev_if when binding a socket to
a v4 mapped address")
