From: Guillaume Nault <gnault@xxxxxxxxxx> [ Upstream commit 91ffd1bae1dafbb9e34b46813f5b058581d9144d ] Ping sockets can't send packets when they're bound to a VRF master device and the output interface is set to a slave device. For example, when net.ipv4.ping_group_range is properly set, so that ping6 can use ping sockets, the following kind of commands fails: $ ip vrf exec red ping6 fe80::854:e7ff:fe88:4bf1%eth1 What happens is that sk->sk_bound_dev_if is set to the VRF master device, but 'oif' is set to the real output device. Since both are set but different, ping_v6_sendmsg() sees their value as inconsistent and fails. Fix this by allowing 'oif' to be a slave device of ->sk_bound_dev_if. This fixes the following kselftest failure: $ ./fcnal-test.sh -t ipv6_ping [...] TEST: ping out, vrf device+address bind - ns-B IPv6 LLA [FAIL] Reported-by: Mirsad Todorovac <mirsad.todorovac@xxxxxxxxxxxx> Closes: https://lore.kernel.org/netdev/b6191f90-ffca-dbca-7d06-88a9788def9c@xxxxxxxxxxxx/ Tested-by: Mirsad Todorovac <mirsad.todorovac@xxxxxxxxxxxx> Fixes: 5e457896986e ("net: ipv6: Fix ping to link-local addresses.") Signed-off-by: Guillaume Nault <gnault@xxxxxxxxxx> Reviewed-by: David Ahern <dsahern@xxxxxxxxxx> Link: https://lore.kernel.org/r/6c8b53108816a8d0d5705ae37bdc5a8322b5e3d9.1686153846.git.gnault@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/ipv6/ping.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c index d5cdba8213a44..49e11bbf390cf 100644 --- a/net/ipv6/ping.c +++ b/net/ipv6/ping.c @@ -101,7 +101,8 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) addr_type = ipv6_addr_type(daddr); if ((__ipv6_addr_needs_scope_id(addr_type) && !oif) || (addr_type & IPV6_ADDR_MAPPED) || - (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if)) + (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if && + l3mdev_master_ifindex_by_index(sock_net(sk), oif) != sk->sk_bound_dev_if)) return -EINVAL; /* TODO: use ip6_datagram_send_ctl to get options from cmsg */ -- 2.39.2
