"New smatch warnings: net/bridge/br_multicast.c:1368 br_ip6_multicast_query() error: we previously assumed 'group' could be null (see line 1349)"
In the rare (sort of broken) case of a query having a Maximum Response Delay of zero, we could create a potential null pointer dereference. Fixing this by skipping the multicast specific MLD Query parsing again if no multicast group address is available. Introduced by dc4eb53a996a78bfb8ea07b47423ff5a3aadc362 ("bridge: adhere to querier election mechanism specified by RFCs") Reported-by: Dan Carpenter <dan.carpen...@oracle.com> Signed-off-by: Linus Lüssing <linus.luess...@web.de> --- net/bridge/br_multicast.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index cd3cf39..876e5fb 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1373,6 +1373,8 @@ static int br_ip6_multicast_query(struct net_bridge *br, br_multicast_query_received(br, port, &br->ip6_other_query, &saddr, max_delay); goto out; + } else if (!group) { + goto out; } mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/