4.18-stable review patch. If anyone has any objections, please let me know.
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From: Nikolay Aleksandrov nikolay@cumulusnetworks.com
commit 0fe5119e267f3e3d8ac206895f5922195ec55a8a upstream.
Recently a check was added which prevents marking of routers with zero source address, but for IPv6 that cannot happen as the relevant RFCs actually forbid such packets: RFC 2710 (MLDv1): "To be valid, the Query message MUST come from a link-local IPv6 Source Address, be at least 24 octets long, and have a correct MLD checksum."
Same goes for RFC 3810.
And also it can be seen as a requirement in ipv6_mc_check_mld_query() which is used by the bridge to validate the message before processing it. Thus any queries with :: source address won't be processed anyway. So just remove the check for zero IPv6 source address from the query processing function.
Fixes: 5a2de63fd1a5 ("bridge: do not add port to router list when receives query with source 0.0.0.0") Signed-off-by: Nikolay Aleksandrov nikolay@cumulusnetworks.com Signed-off-by: David S. Miller davem@davemloft.net Cc: Hangbin Liu liuhangbin@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/bridge/br_multicast.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
--- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1426,8 +1426,7 @@ static void br_multicast_query_received( * is 0.0.0.0 should not be added to router port list. */ if ((saddr->proto == htons(ETH_P_IP) && saddr->u.ip4) || - (saddr->proto == htons(ETH_P_IPV6) && - !ipv6_addr_any(&saddr->u.ip6))) + saddr->proto == htons(ETH_P_IPV6)) br_multicast_mark_router(br, port); }