netfilter: nat: fix soft lockup when most ports are used

First patch removes old rovers, they are inherently racy and cause packet drops/delays.

Second patch avoids iterating entire range of ports: It takes way too long when most tuples are in use.

First patch is slightly mangled; nf_nat_proto_common.c needs minor adjustment in context.

Florian Westphal (2):
netfilter: nat: remove l4 protocol port rovers
netfilter: nat: limit port clash resolution attempts

 include/net/netfilter/nf_nat_l4proto.h |  2 +-
 net/netfilter/nf_nat_proto_common.c    | 36 ++++++++++++++++++--------
 net/netfilter/nf_nat_proto_dccp.c      |  5 +---
 net/netfilter/nf_nat_proto_sctp.c      |  5 +---
 net/netfilter/nf_nat_proto_tcp.c       |  5 +---
 net/netfilter/nf_nat_proto_udp.c       | 10 ++-----
 6 files changed, 31 insertions(+), 32 deletions(-)

2.34.1