net: bridge: Bounce invalid boolopts

The bridge driver currently tolerates options that it does not recognize.
Instead, it should bounce them.

Fixes: a428afe ("net: bridge: add support for user-controlled bool options")
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/e6fdca3b5a8d54183fbda075daffef38bdd7ddce.1757070067.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: pmachata

net/bridge/br.c

@@ -324,6 +324,13 @@ int br_boolopt_multi_toggle(struct net_bridge *br,
 	int err = 0;
 	int opt_id;
 
+	opt_id = find_next_bit(&bitmap, BITS_PER_LONG, BR_BOOLOPT_MAX);
+	if (opt_id != BITS_PER_LONG) {
+		NL_SET_ERR_MSG_FMT_MOD(extack, "Unknown boolean option %d",
+				       opt_id);
+		return -EINVAL;
+	}
+
 	for_each_set_bit(opt_id, &bitmap, BR_BOOLOPT_MAX) {
 		bool on = !!(bm->optval & BIT(opt_id));