4.20-stable review patch. If anyone has any objections, please let me know.
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From: Rundong Ge rdong.ge@gmail.com
[ Upstream commit 17ab4f61b8cd6f9c38e9d0b935d86d73b5d0d2b5 ]
The unbalance of master's promiscuity or allmulti will happen after ifdown and ifup a slave interface which is in a bridge.
When we ifdown a slave interface , both the 'dsa_slave_close' and 'dsa_slave_change_rx_flags' will clear the master's flags. The flags of master will be decrease twice. In the other hand, if we ifup the slave interface again, since the slave's flags were cleared the 'dsa_slave_open' won't set the master's flag, only 'dsa_slave_change_rx_flags' that triggered by 'br_add_if' will set the master's flags. The flags of master is increase once.
Only propagating flag changes when a slave interface is up makes sure this does not happen. The 'vlan_dev_change_rx_flags' had the same problem and was fixed, and changes here follows that fix.
Fixes: 91da11f870f0 ("net: Distributed Switch Architecture protocol support") Signed-off-by: Rundong Ge rdong.ge@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/dsa/slave.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)
--- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -140,11 +140,14 @@ static int dsa_slave_close(struct net_de static void dsa_slave_change_rx_flags(struct net_device *dev, int change) { struct net_device *master = dsa_slave_to_master(dev); - - if (change & IFF_ALLMULTI) - dev_set_allmulti(master, dev->flags & IFF_ALLMULTI ? 1 : -1); - if (change & IFF_PROMISC) - dev_set_promiscuity(master, dev->flags & IFF_PROMISC ? 1 : -1); + if (dev->flags & IFF_UP) { + if (change & IFF_ALLMULTI) + dev_set_allmulti(master, + dev->flags & IFF_ALLMULTI ? 1 : -1); + if (change & IFF_PROMISC) + dev_set_promiscuity(master, + dev->flags & IFF_PROMISC ? 1 : -1); + } }
static void dsa_slave_set_rx_mode(struct net_device *dev)