[PATCH 4.9 18/19] ping: fix address binding wrt vrf

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Nicolas Dichtel <nicolas.dichtel@6wind.com>

commit e1a7ac6f3ba6e157adcd0ca94d92a401f1943f56 upstream.

When ping_group_range is updated, 'ping' uses the DGRAM ICMP socket,
instead of an IP raw socket. In this case, 'ping' is unable to bind its
socket to a local address owned by a vrflite.

Before the patch:
$ sysctl -w net.ipv4.ping_group_range='0  2147483647'
$ ip link add blue type vrf table 10
$ ip link add foo type dummy
$ ip link set foo master blue
$ ip link set foo up
$ ip addr add 192.168.1.1/24 dev foo
$ ip addr add 2001::1/64 dev foo
$ ip vrf exec blue ping -c1 -I 192.168.1.1 192.168.1.2
ping: bind: Cannot assign requested address
$ ip vrf exec blue ping6 -c1 -I 2001::1 2001::2
ping6: bind icmp socket: Cannot assign requested address

CC: stable@vger.kernel.org
Fixes: 1b69c6d0ae90 ("net: Introduce L3 Master device abstraction")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/ping.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -302,6 +302,7 @@ static int ping_check_bind_addr(struct s
 	struct net *net = sock_net(sk);
 	if (sk->sk_family == AF_INET) {
 		struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
+		u32 tb_id = RT_TABLE_LOCAL;
 		int chk_addr_ret;
 
 		if (addr_len < sizeof(*addr))
@@ -315,7 +316,8 @@ static int ping_check_bind_addr(struct s
 		pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
 			 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
 
-		chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
+		tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
+		chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
 
 		if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
 			chk_addr_ret = RTN_LOCAL;
@@ -355,6 +357,14 @@ static int ping_check_bind_addr(struct s
 			if (!dev) {
 				rcu_read_unlock();
 				return -ENODEV;
+			}
+		}
+
+		if (!dev && sk->sk_bound_dev_if) {
+			dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
+			if (!dev) {
+				rcu_read_unlock();
+				return -ENODEV;
 			}
 		}
 		has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,