On 02/07/2021 15:07, Wolfgang Bumiller wrote:

Since commit 2796d0c648c9 ("bridge: Automatically manage
port promiscuous mode.")
bridges with `vlan_filtering 1` and only 1 auto-port don't
set IFF_PROMISC for unicast-filtering-capable ports.

Normally on port changes `br_manage_promisc` is called to
update the promisc flags and unicast filters if necessary,
but it cannot distinguish between *new* ports and ones
losing their promisc flag, and new ports end up not
receiving the MAC address list.

Fix this by calling `br_fdb_sync_static` in `br_add_if`
after the port promisc flags are updated and the unicast
filter was supposed to have been filled.

Fixes: 2796d0c648c9 ("bridge: Automatically manage port promiscuous mode.")
Signed-off-by: Wolfgang Bumiller <redacted>
---
Changes to v2:
  * Added 'fdb_synced' boolean to only unsync on error if it was
    actually synced.
    `br_fdb_sync_static()` already unrolls changes if it encounters an
    error in the middle, so only a successful call will trigger the
    unsync.
    I opted for the explicit error handling as I felt that avoiding the
    error cleanup by moving the code down might be more easily missed in
    future changes (I just felt safer this way), plus, it's closer to
    the call which would normally be responsible for doing this which
    felt more natural to me.

    I hope this is fine, otherwise I can still move it :-)

 net/bridge/br_if.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

Looks good to me, thanks!
Acked-by: Nikolay Aleksandrov <redacted>