[PATCH 4.14 10/29] bonding: fix ad_actor_system option setting to default

Greg Kroah-Hartman
2021-12-27T15:31:16Z

From: Fernando Fernandez Mancera <ffmancera@riseup.net>

[ Upstream commit 1c15b05baea71a5ff98235783e3e4ad227760876 ]

When 802.3ad bond mode is configured the ad_actor_system option is set to
"00:00:00:00:00:00". But when trying to set the all-zeroes MAC as actors'
system address it was failing with EINVAL.

An all-zeroes ethernet address is valid, only multicast addresses are not
valid values.

Fixes: 171a42c38c6e ("bonding: add netlink support for sys prio, actor sys mac, and port key")
Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Link: https://lore.kernel.org/r/20211221111345.2462-1-ffmancera@riseup.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
Documentation/networking/bonding.txt | 11 ++++++-----
drivers/net/bonding/bond_options.c | 2 +-
2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt
index 9ba04c0bab8db..f5d78c8005341 100644
--- a/Documentation/networking/bonding.txt
+++ b/Documentation/networking/bonding.txt
@@ -191,11 +191,12 @@ ad_actor_sys_prio
ad_actor_system

In an AD system, this specifies the mac-address for the actor in
- protocol packet exchanges (LACPDUs). The value cannot be NULL or
- multicast. It is preferred to have the local-admin bit set for this
- mac but driver does not enforce it. If the value is not given then
- system defaults to using the masters' mac address as actors' system
- address.
+ protocol packet exchanges (LACPDUs). The value cannot be a multicast
+ address. If the all-zeroes MAC is specified, bonding will internally
+ use the MAC of the bond itself. It is preferred to have the
+ local-admin bit set for this mac but driver does not enforce it. If
+ the value is not given then system defaults to using the masters'
+ mac address as actors' system address.

This parameter has effect only in 802.3ad mode and is available through
SysFs interface.
diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
index f24df859f0a7e..1e81b1cafae35 100644
--- a/drivers/net/bonding/bond_options.c
+++ b/drivers/net/bonding/bond_options.c
@@ -1443,7 +1443,7 @@ static int bond_option_ad_actor_system_set(struct bonding *bond,
mac = (u8 *)&newval->value;
}

- if (!is_valid_ether_addr(mac))
+ if (is_multicast_ether_addr(mac))
goto err;

netdev_dbg(bond->dev, "Setting ad_actor_system to %pM\n", mac);
--
2.34.1