| Message ID | 20190729092841.4260-1-nikolay@cumulusnetworks.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net,v2] net: bridge: delete local fdb on device init failure | expand |
From: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Date: Mon, 29 Jul 2019 12:28:41 +0300 > On initialization failure we have to delete the local fdb which was > inserted due to the default pvid creation. This problem has been present > since the inception of default_pvid. Note that currently there are 2 cases: > 1) in br_dev_init() when br_multicast_init() fails > 2) if register_netdevice() fails after calling ndo_init() > > This patch takes care of both since br_vlan_flush() is called on both > occasions. Also the new fdb delete would be a no-op on normal bridge > device destruction since the local fdb would've been already flushed by > br_dev_delete(). This is not an issue for ports since nbp_vlan_init() is > called last when adding a port thus nothing can fail after it. > > Reported-by: syzbot+88533dc8b582309bf3ee@syzkaller.appspotmail.com > Fixes: 5be5a2df40f0 ("bridge: Add filtering support for default_pvid") > Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> > --- > v2: reworded the commit message and comment so they're not plural, we're > talking about a single bridge local fdb added on the init vlan creation > of the default pvid > > Tested with the provided reproducer and can no longer trigger the leak. > Also tested the br_multicast_init() failure manually by making it always > return an error. Applied and queued up for -stable, thank you.
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c index 021cc9f66804..3e6a702e4c21 100644 --- a/net/bridge/br_vlan.c +++ b/net/bridge/br_vlan.c @@ -715,6 +715,11 @@ void br_vlan_flush(struct net_bridge *br) ASSERT_RTNL(); + /* delete auto-added default pvid local fdb before flushing vlans + * otherwise it will be leaked on bridge device init failure + */ + br_fdb_delete_by_port(br, NULL, 0, 1); + vg = br_vlan_group(br); __vlan_flush(vg); RCU_INIT_POINTER(br->vlgrp, NULL);
On initialization failure we have to delete the local fdb which was inserted due to the default pvid creation. This problem has been present since the inception of default_pvid. Note that currently there are 2 cases: 1) in br_dev_init() when br_multicast_init() fails 2) if register_netdevice() fails after calling ndo_init() This patch takes care of both since br_vlan_flush() is called on both occasions. Also the new fdb delete would be a no-op on normal bridge device destruction since the local fdb would've been already flushed by br_dev_delete(). This is not an issue for ports since nbp_vlan_init() is called last when adding a port thus nothing can fail after it. Reported-by: syzbot+88533dc8b582309bf3ee@syzkaller.appspotmail.com Fixes: 5be5a2df40f0 ("bridge: Add filtering support for default_pvid") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> --- v2: reworded the commit message and comment so they're not plural, we're talking about a single bridge local fdb added on the init vlan creation of the default pvid Tested with the provided reproducer and can no longer trigger the leak. Also tested the br_multicast_init() failure manually by making it always return an error. net/bridge/br_vlan.c | 5 +++++ 1 file changed, 5 insertions(+)