From: Nikolay Aleksandrov nikolay@nvidia.com
commit fac3cb82a54a4b7c49c932f96ef196cf5774344c upstream.
When I added IGMPv3 support I decided to follow the RFC for computing the GMI dynamically: " 8.4. Group Membership Interval
The Group Membership Interval is the amount of time that must pass before a multicast router decides there are no more members of a group or a particular source on a network.
This value MUST be ((the Robustness Variable) times (the Query Interval)) plus (one Query Response Interval)."
But that actually is inconsistent with how the bridge used to compute it for IGMPv2, where it was user-configurable that has a correct default value but it is up to user-space to maintain it. This would make it consistent with the other timer values which are also maintained correct by the user instead of being dynamically computed. It also changes back to the previous user-expected GMI behaviour for IGMPv3 queries which were supported before IGMPv3 was added. Note that to properly compute it dynamically we would need to add support for "Robustness Variable" which is currently missing.
Reported-by: Hangbin Liu liuhangbin@gmail.com Fixes: 0436862e417e ("net: bridge: mcast: support for IGMPv3/MLDv2 ALLOW_NEW_SOURCES report") Signed-off-by: Nikolay Aleksandrov nikolay@nvidia.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/bridge/br_private.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
--- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -931,9 +931,7 @@ static inline unsigned long br_multicast
static inline unsigned long br_multicast_gmi(const struct net_bridge *br) { - /* use the RFC default of 2 for QRV */ - return 2 * br->multicast_query_interval + - br->multicast_query_response_interval; + return br->multicast_membership_interval; } #else static inline int br_multicast_rcv(struct net_bridge *br,