linux-toradex.git/net/bridge/br_fdb.c, branch v4.4.63

bridge: Don't insert unnecessary local fdb entry on changing mac address

2016-06-24T17:18:17+00:00

[ Upstream commit 0b148def403153a4d1565f1640356cb78ce5109f ]

The missing br_vlan_should_use() test caused creation of an unneeded
local fdb entry on changing mac address of a bridge device when there is
a vlan which is configured on a bridge port but not on the bridge
device.

Fixes: 2594e9064a57 ("bridge: vlan: add per-vlan struct and move to rhashtables")
Signed-off-by: Toshiaki Makita 
Acked-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: set is_local and is_static before fdb entry is added to the fdb hashtable

2015-10-30T03:13:05+00:00

Problem Description:
We can add fdbs pointing to the bridge with NULL ->dst but that has a
few race conditions because br_fdb_insert() is used which first creates
the fdb and then, after the fdb has been published/linked, sets
"is_local" to 1 and in that time frame if a packet arrives for that fdb
it may see it as non-local and either do a NULL ptr dereference in
br_forward() or attach the fdb to the port where it arrived, and later
br_fdb_insert() will make it local thus getting a wrong fdb entry.
Call chain br_handle_frame_finish() -> br_forward():
But in br_handle_frame_finish() in order to call br_forward() the dst
should not be local i.e. skb != NULL, whenever the dst is
found to be local skb is set to NULL so we can't forward it,
and here comes the problem since it's running only
with RCU when forwarding packets it can see the entry before "is_local"
is set to 1 and actually try to dereference NULL.
The main issue is that if someone sends a packet to the switch while
it's adding the entry which points to the bridge device, it may
dereference NULL ptr. This is needed now after we can add fdbs
pointing to the bridge.  This poses a problem for
br_fdb_update() as well, while someone's adding a bridge fdb, but
before it has is_local == 1, it might get moved to a port if it comes
as a source mac and then it may get its "is_local" set to 1

This patch changes fdb_create to take is_local and is_static as
arguments to set these values in the fdb entry before it is added to the
hash. Also adds null check for port in br_forward.

Fixes: 3741873b4f73 ("bridge: allow adding of fdb entries pointing to the bridge device")
Reported-by: Nikolay Aleksandrov 
Signed-off-by: Roopa Prabhu 
Reviewed-by: Nikolay Aleksandrov 
Acked-by: Stephen Hemminger 
Signed-off-by: David S. Miller

bridge: defer switchdev fdb del call in fdb_del_external_learn

2015-10-15T13:09:50+00:00

Since spinlock is held here, defer the switchdev operation. Also, ensure
that defered switchdev ops are processed before port master device
is unlinked.

Signed-off-by: Jiri Pirko 
Signed-off-by: David S. Miller

switchdev: remove pointers from switchdev objects

2015-10-15T13:09:49+00:00

When object is used in deferred work, we cannot use pointers in
switchdev object structures because the memory they point at may be already
used by someone else. So rather do local copy of the value.

Signed-off-by: Jiri Pirko 
Acked-by: Scott Feldman 
Reviewed-by: John Fastabend 
Signed-off-by: David S. Miller

bridge: allow adding of fdb entries pointing to the bridge device

2015-10-12T12:11:58+00:00

This patch enables adding of fdb entries pointing to the bridge device.
This can be used to propagate mac address of vlan interfaces
configured on top of the vlan filtering bridge.

Before:
$bridge fdb add 44:38:39:00:27:9f dev bridge
RTNETLINK answers: Invalid argument

After:
$bridge fdb add 44:38:39:00:27:9f dev bridge

Signed-off-by: Roopa Prabhu 
Reviewed-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

switchdev: push object ID back to object structure

2015-10-03T11:49:40+00:00

Suggested-by: Scott Feldman 
Signed-off-by: Jiri Pirko 
Acked-by: Scott Feldman 
Reviewed-by: Vivien Didelot 
Signed-off-by: David S. Miller

switchdev: bring back switchdev_obj and use it as a generic object param

2015-10-03T11:49:39+00:00

Replace "void *obj" with a generic structure. Introduce couple of
helpers along that.

Signed-off-by: Jiri Pirko 
Acked-by: Scott Feldman 
Reviewed-by: Vivien Didelot 
Signed-off-by: David S. Miller

switchdev: rename switchdev_obj_fdb to switchdev_obj_port_fdb

2015-10-03T11:49:39+00:00

Make the struct name in sync with object id name.

Suggested-by: Vivien Didelot 
Signed-off-by: Jiri Pirko 
Acked-by: Scott Feldman 
Reviewed-by: Vivien Didelot 
Signed-off-by: David S. Miller

switchdev: rename SWITCHDEV_OBJ_* enum values to SWITCHDEV_OBJ_ID_*

2015-10-03T11:49:36+00:00

Suggested-by: Vivien Didelot 
Signed-off-by: Jiri Pirko 
Acked-by: Scott Feldman 
Reviewed-by: Vivien Didelot 
Signed-off-by: David S. Miller

net: switchdev: abstract object in add/del ops

2015-09-30T04:31:59+00:00

Similar to the notifier_call callback of a notifier_block, change the
function signature of switchdev add and del operations to:

    int switchdev_port_obj_add/del(struct net_device *dev,
                                   enum switchdev_obj_id id, void *obj);

This allows the caller to pass a specific switchdev_obj_* structure
instead of the generic switchdev_obj one.

Drivers implementation of these operations and switchdev have been
changed accordingly.

Signed-off-by: Vivien Didelot 
Signed-off-by: David S. Miller