The value dhcpv6_msg_type points at is used as index to dhcpv6_timeouts array, so upper boundary check has to treat a value of ARRAY_SIZE(dhcpv6_timeouts) as invalid. Fixes: 36118bfc4901b ("conntrackd: helpers: add DHCPv6 helper") Signed-off-by: Phil Sutter <phil@xxxxxx> --- src/helpers/dhcpv6.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/helpers/dhcpv6.c b/src/helpers/dhcpv6.c index 73632ec181a95..f87b6cebfe157 100644 --- a/src/helpers/dhcpv6.c +++ b/src/helpers/dhcpv6.c @@ -72,7 +72,7 @@ dhcpv6_helper_cb(struct pkt_buff *pkt, uint32_t protoff, return NF_ACCEPT; dhcpv6_msg_type = pktb_network_header(pkt) + protoff + sizeof(struct udphdr); - if (*dhcpv6_msg_type > ARRAY_SIZE(dhcpv6_timeouts)) { + if (*dhcpv6_msg_type >= ARRAY_SIZE(dhcpv6_timeouts)) { printf("Dropping DHCPv6 message with bad type %u\n", *dhcpv6_msg_type); return NF_DROP; -- 2.20.1