Commit 8b61fba5 authored Aug 18, 2020 by Alvin Šipraga Committed by David S. Miller Aug 18, 2020

macvlan: validate setting of multiple remote source MAC addresses



Remote source MAC addresses can be set on a 'source mode' macvlan
interface via the IFLA_MACVLAN_MACADDR_DATA attribute. This commit
tightens the validation of these MAC addresses to match the validation
already performed when setting or adding a single MAC address via the
IFLA_MACVLAN_MACADDR attribute.

iproute2 uses IFLA_MACVLAN_MACADDR_DATA for its 'macvlan macaddr set'
command, and IFLA_MACVLAN_MACADDR for its 'macvlan macaddr add' command,
which demonstrates the inconsistent behaviour that this commit
addresses:

 # ip link add link eth0 name macvlan0 type macvlan mode source
 # ip link set link dev macvlan0 type macvlan macaddr add 01:00:00:00:00:00
 RTNETLINK answers: Cannot assign requested address
 # ip link set link dev macvlan0 type macvlan macaddr set 01:00:00:00:00:00
 # ip -d link show macvlan0
 5: macvlan0@eth0: <BROADCAST,MULTICAST,DYNAMIC,UP,LOWER_UP> mtu 1500 ...
     link/ether 2e:ac:fd:2d:69:f8 brd ff:ff:ff:ff:ff:ff promiscuity 0
     macvlan mode source remotes (1) 01:00:00:00:00:00 numtxqueues 1 ...

With this change, the 'set' command will (rightly) fail in the same way
as the 'add' command.

Signed-off-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 06a4ec1d

drivers/net/macvlan.c

+17 −4

Original line number	Diff line number	Diff line
		@@ -1269,6 +1269,9 @@ static void macvlan_port_destroy(struct net_device *dev)
		static int macvlan_validate(struct nlattr tb[], struct nlattr data[],
		struct netlink_ext_ack *extack)
		{
		struct nlattr nla, head;
		int rem, len;

		if (tb[IFLA_ADDRESS]) {
		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
		return -EINVAL;
		@@ -1316,6 +1319,20 @@ static int macvlan_validate(struct nlattr tb[], struct nlattr data[],
		return -EADDRNOTAVAIL;
		}

		if (data[IFLA_MACVLAN_MACADDR_DATA]) {
		head = nla_data(data[IFLA_MACVLAN_MACADDR_DATA]);
		len = nla_len(data[IFLA_MACVLAN_MACADDR_DATA]);

		nla_for_each_attr(nla, head, len, rem) {
		if (nla_type(nla) != IFLA_MACVLAN_MACADDR \|\|
		nla_len(nla) != ETH_ALEN)
		return -EINVAL;

		if (!is_valid_ether_addr(nla_data(nla)))
		return -EADDRNOTAVAIL;
		}
		}

		if (data[IFLA_MACVLAN_MACADDR_COUNT])
		return -EINVAL;

		@@ -1372,10 +1389,6 @@ static int macvlan_changelink_sources(struct macvlan_dev *vlan, u32 mode,
		len = nla_len(data[IFLA_MACVLAN_MACADDR_DATA]);

		nla_for_each_attr(nla, head, len, rem) {
		if (nla_type(nla) != IFLA_MACVLAN_MACADDR \|\|
		nla_len(nla) != ETH_ALEN)
		continue;

		addr = nla_data(nla);
		ret = macvlan_hash_add_source(vlan, addr);
		if (ret)

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