diff options
Diffstat (limited to 'net/ipv4/netfilter/ip_nat_proto_udp.c')
| -rw-r--r-- | net/ipv4/netfilter/ip_nat_proto_udp.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/ip_nat_proto_udp.c b/net/ipv4/netfilter/ip_nat_proto_udp.c index 5ced0877b32f..dfd521672891 100644 --- a/net/ipv4/netfilter/ip_nat_proto_udp.c +++ b/net/ipv4/netfilter/ip_nat_proto_udp.c @@ -8,6 +8,7 @@ #include <linux/types.h> #include <linux/init.h> +#include <linux/random.h> #include <linux/netfilter.h> #include <linux/ip.h> #include <linux/udp.h> @@ -74,6 +75,10 @@ udp_unique_tuple(struct ip_conntrack_tuple *tuple, range_size = ntohs(range->max.udp.port) - min + 1; } + /* Start from random port to avoid prediction */ + if (range->flags & IP_NAT_RANGE_PROTO_RANDOM) + port = net_random(); + for (i = 0; i < range_size; i++, port++) { *portptr = htons(min + port % range_size); if (!ip_nat_used_tuple(tuple, conntrack)) |