4.19-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 59f997b088d26a774958cb7b17b0763cd82de7ec ]
A MAC address must be unique among all the macvlan devices with the same lower device. The only exception is the passthru [sic] mode, which shares the lower device address.
When duplicate addresses are detected, EBUSY is returned when bringing the interface up:
# ip link add macvlan0 link eth0 type macvlan # read addr </sys/class/net/eth0/address # ip link set macvlan0 address $addr # ip link set macvlan0 up RTNETLINK answers: Device or resource busy
Use correct error code which is EADDRINUSE, and do the check also earlier, on address change:
# ip link set macvlan0 address $addr RTNETLINK answers: Address already in use
Signed-off-by: Matteo Croce mcroce@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/macvlan.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index cfda146f3b3b..6372cdc4a510 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -608,7 +608,7 @@ static int macvlan_open(struct net_device *dev) goto hash_add; }
- err = -EBUSY; + err = -EADDRINUSE; if (macvlan_addr_busy(vlan->port, dev->dev_addr)) goto out;
@@ -706,7 +706,7 @@ static int macvlan_sync_address(struct net_device *dev, unsigned char *addr) } else { /* Rehash and update the device filters */ if (macvlan_addr_busy(vlan->port, addr)) - return -EBUSY; + return -EADDRINUSE;
if (!macvlan_passthru(port)) { err = dev_uc_add(lowerdev, addr); @@ -747,6 +747,9 @@ static int macvlan_set_mac_address(struct net_device *dev, void *p) return dev_set_mac_address(vlan->lowerdev, addr); }
+ if (macvlan_addr_busy(vlan->port, addr->sa_data)) + return -EADDRINUSE; + return macvlan_sync_address(dev, addr->sa_data); }