Neal Cardwell 9f950415e4 tcp: fix child sockets to use system default congestion control if not set ... Linux 3.17 and earlier are explicitly engineered so that if the app doesn't specifically request a CC module on a listener before the SYN arrives, then the child gets the system default CC when the connection is established. See tcp_init_congestion_control() in 3.17 or earlier, which says "if no choice made yet assign the current value set as default". The change ("net: tcp: assign tcp cong_ops when tcp sk is created") altered these semantics, so that children got their parent listener's congestion control even if the system default had changed after the listener was created. This commit returns to those original semantics from 3.17 and earlier, since they are the original semantics from 2007 in 4d4d3d1e8 ("[TCP]: Congestion control initialization."), and some Linux congestion control workflows depend on that. In summary, if a listener socket specifically sets TCP_CONGESTION to "x", or the route locks the CC module to "x", then the child gets "x". Otherwise the child gets current system default from net.ipv4.tcp_congestion_control. That's the behavior in 3.17 and earlier, and this commit restores that. Fixes: 55d8694fa8 ("net: tcp: assign tcp cong_ops when tcp sk is created") Cc: Florian Westphal <fw@strlen.de> Cc: Daniel Borkmann <dborkman@redhat.com> Cc: Glenn Judd <glenn.judd@morganstanley.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>		2015-05-31 21:49:14 -07:00
..
9p	9p: switch p9_client_read() to passing struct iov_iter *	2015-04-11 22:28:27 -04:00
bluetooth	Bluetooth: Read LE remote features during connection establishment	2015-04-09 08:36:54 +03:00
caif	caif: fix a signedness bug in cfpkt_iterate()	2015-02-20 17:35:14 -05:00
irda	irda: Convert function pointer arrays and uses to const	2014-12-10 15:33:16 -05:00
iucv	…
netfilter	netfilter: nf_tables: mark stateful expressions	2015-04-13 20:12:31 +02:00
netns	netns: remove BUG_ONs from net_generic()	2015-04-17 15:21:48 -04:00
nfc	nfc: nci: Add comment to explain NCI_HCI_MAX_PIPES	2015-04-06 00:19:05 +02:00
phonet	…
sctp	sctp: Fix mangled IPv4 addresses on a IPv6 listening socket	2015-05-27 14:15:26 -04:00
tc_act	act_bpf: add initial eBPF support for actions	2015-03-20 19:10:44 -04:00
6lowpan.h	ieee802154: 6lowpan: rename process_data and lowpan_process_data	2014-10-27 15:51:16 +01:00
Space.h	…
act_api.h	net_sched: act: refuse to remove bound action outside	2014-02-12 19:23:32 -05:00
addrconf.h	net: ipv6: allow explicitly choosing optimistic addresses	2015-02-05 15:37:41 -08:00
af_ieee802154.h	ieee802154: mac802154: remove FSF address	2014-10-25 08:07:30 +02:00
af_rxrpc.h	…
af_unix.h	…
af_vsock.h	net: Remove iocb argument from sendmsg and recvmsg	2015-03-02 13:06:31 -05:00
ah.h	ipsec: Remove obsolete MAX_AH_AUTH_LEN	2014-09-18 10:54:36 +02:00
arp.h	neigh: Factor out ___neigh_lookup_noref	2015-03-04 00:23:23 -05:00
atmclip.h	…
ax25.h	ax25: Stop using magic neighbour cache operations.	2015-03-03 14:44:41 -05:00
ax88796.h	…
bond_3ad.h	bonding: Implement port churn-machine (AD standard 43.4.17).	2015-02-24 16:05:48 -05:00
bond_alb.h	net: Move bonding headers under include/net	2014-11-10 13:27:49 -05:00
bond_options.h	net: Move bonding headers under include/net	2014-11-10 13:27:49 -05:00
bonding.h	net/bonding: Make DRV macros private	2015-04-26 22:59:53 -04:00
busy_poll.h	…
cfg80211-wext.h	…
cfg80211.h	cfg80211: move IE split utilities here from mac80211	2015-04-07 13:56:41 +02:00
cfg802154.h	cfg802154: pass name_assign_type to rdev_add_virtual_intf()	2015-04-30 18:48:10 +02:00
checksum.h	net: Fix remcsum in GRO path to not change packet	2015-02-11 15:12:09 -08:00
cipso_ipv4.h	cipso: don't use IPCB() to locate the CIPSO IP option	2015-02-11 14:46:37 -05:00
cls_cgroup.h	cgroup: clean up cgroup_subsys names and initialization	2014-02-08 10:36:58 -05:00
codel.h	codel: fix maxpacket/mtu confusion	2015-05-03 22:17:40 -04:00
compat.h	net: switch importing msghdr from userland to {compat_,}import_iovec()	2015-04-09 00:02:26 -04:00
datalink.h	net: Move prototype declaration to header file include/net/datalink.h from net/ipx/af_ipx.c	2014-02-09 17:32:50 -08:00
dcbevent.h	…
dcbnl.h	net/dcb: Add IEEE QCN attribute	2015-03-06 21:50:02 -05:00
dn.h	net: Move prototype declaration to header file include/net/dn.h from net/decnet/af_decnet.c	2014-02-09 17:32:49 -08:00
dn_dev.h	…
dn_fib.h	…
dn_neigh.h	netfilter: Pass socket pointer down through okfn().	2015-04-07 15:25:55 -04:00
dn_nsp.h	…
dn_route.h	net: Move prototype declaration to appropriate header file from decnet/af_decnet.c	2014-02-09 17:32:49 -08:00
dsa.h	net: dsa: Add basic framework to support ndo_fdb functions	2015-03-29 13:23:54 -07:00
dsfield.h	…
dst.h	xfrm: release dst_orig in case of error in xfrm_lookup()	2015-02-12 07:10:56 +01:00
dst_ops.h	net: Remove protocol from struct dst_ops	2015-03-09 16:06:10 -04:00
esp.h	…
ethoc.h	net: ethoc: set up MII management bus clock	2014-02-04 20:19:51 -08:00
fib_rules.h	net: Kill hold_net release_net	2015-03-12 14:39:40 -04:00
firewire.h	…
flow.h	ipv4, fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif	2014-04-16 15:05:11 -04:00
flow_keys.h	flow_keys: n_proto type should be __be16	2015-02-05 00:40:22 -08:00
flowcache.h	flowcache: Make flow cache name space aware	2014-02-12 07:02:11 +01:00
fou.h	ip_tunnel: Ops registration for secondary encap (fou, gue)	2014-11-12 15:01:35 -05:00
garp.h	…
gen_stats.h	net: sched: enable per cpu qstats	2014-09-30 01:02:26 -04:00
genetlink.h	net: Introduce possible_net_t	2015-03-12 14:39:40 -04:00
geneve.h	openvswitch: Add support for checksums on UDP tunnels.	2015-01-28 23:04:15 -08:00
gre.h	gre: Call gso_make_checksum	2014-06-04 22:46:38 -07:00
gro_cells.h	ip_tunnel: Create percpu gro_cell	2015-01-18 01:56:32 -05:00
gue.h	gue: Protocol constants for remote checksum offload	2014-11-05 16:30:03 -05:00
icmp.h	…
ieee80211_radiotap.h	mac80211: propagate STBC / LDPC flags to radiotap	2014-02-06 09:34:58 +01:00
ieee802154_netdev.h	ieee802154: rework cca setting	2014-12-19 00:19:23 +01:00
if_inet6.h	ipv6: do retries on stable privacy addresses	2015-03-23 22:12:09 -04:00
inet6_connection_sock.h	inet: get rid of central tcp/dccp listener timer	2015-03-20 12:40:25 -04:00
inet6_hashtables.h	ipv6: get rid of __inet6_hash()	2015-03-18 22:00:35 -04:00
inet_common.h	net: Remove iocb argument from sendmsg and recvmsg	2015-03-02 13:06:31 -05:00
inet_connection_sock.h	tcp: fix child sockets to use system default congestion control if not set	2015-05-31 21:49:14 -07:00
inet_ecn.h	tunnel: fix RFC number in comment for INET_ECN_decapsulate()	2014-05-07 15:30:52 -04:00
inet_frag.h	percpu_counter: add @gfp to percpu_counter_init()	2014-09-08 09:51:29 +09:00
inet_hashtables.h	inet: get rid of last __inet_hash_connect() argument	2015-03-18 22:00:35 -04:00
inet_sock.h	inet: fix request sock refcounting	2015-03-17 22:02:29 -04:00
inet_timewait_sock.h	tcp/dccp: get rid of central timewait timer	2015-04-13 16:40:05 -04:00
inetpeer.h	tcp: simplify inetpeer_addr_base use	2015-03-31 13:58:35 -04:00
ip.h	netfilter: Pass socket pointer down through okfn().	2015-04-07 15:25:55 -04:00
ip6_checksum.h	net: add gro_compute_pseudo functions	2014-08-24 18:09:23 -07:00
ip6_fib.h	net: fib6: convert cfg metric to u32 outside of table write lock	2015-01-05 22:55:24 -05:00
ip6_route.h	netfilter: Pass socket pointer down through okfn().	2015-04-07 15:25:55 -04:00
ip6_tunnel.h	udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb().	2015-04-07 15:29:08 -04:00
ip_fib.h	ipv4: FIB Local/MAIN table collapse	2015-03-11 16:22:14 -04:00
ip_tunnels.h	ipip,gre,vti,sit: implement ndo_get_iflink	2015-04-02 14:05:00 -04:00
ip_vs.h	net: Introduce possible_net_t	2015-03-12 14:39:40 -04:00
ipcomp.h	…
ipconfig.h	…
ipv6.h	net: remove extra newlines	2015-04-07 22:24:37 -04:00
ipx.h	switch ipxrtr_route_packet() from iovec to msghdr	2014-11-24 04:28:49 -05:00
iw_handler.h	wext: add checked wrappers for adding events/points to streams	2015-02-28 21:31:12 +01:00
lapb.h	…
lib80211.h	lib80211: remove unused print_ssid()	2014-10-14 02:18:27 +02:00
llc.h	…
llc_c_ac.h	…
llc_c_ev.h	…
llc_c_st.h	llc: Make llc_conn_ev_qfyr_t function pointer arrays const	2014-12-10 15:21:24 -05:00
llc_conn.h	…
llc_if.h	…
llc_pdu.h	…
llc_s_ac.h	…
llc_s_ev.h	…
llc_s_st.h	llc: Make llc_sap_action_t function pointer arrays const	2014-12-10 15:21:24 -05:00
llc_sap.h	…
mac80211.h	mac80211: Fix mac80211.h docbook comments	2015-05-28 14:37:43 +02:00
mac802154.h	mac802154: add description to mac802154 APIs	2015-04-30 18:48:09 +02:00
mip6.h	…
mld.h	ipv6: mld: answer mldv2 queries with mldv1 reports in mldv1 fallback	2014-09-22 16:23:15 -04:00
mpls.h	openvswitch: Add basic MPLS support to kernel	2014-11-05 23:52:33 -08:00
mrp.h	…
ndisc.h	neigh: Factor out ___neigh_lookup_noref	2015-03-04 00:23:23 -05:00
neighbour.h	net: neighbour: Add mcast_resolicit to configure the number of multicast resolicitations in PROBE state.	2015-03-20 21:47:40 -04:00
net_namespace.h	net: Introduce possible_net_t	2015-03-12 14:39:40 -04:00
net_ratelimit.h	…
netevent.h	…
netlabel.h	netlabel: fix the netlbl_catmap_setlong() dummy function	2014-08-07 20:55:21 -04:00
netlink.h	netlink: implement nla_get_in_addr and nla_get_in6_addr	2015-03-31 13:58:35 -04:00
netprio_cgroup.h	cgroup: clean up cgroup_subsys names and initialization	2014-02-08 10:36:58 -05:00
netrom.h	…
nexthop.h	…
nl802154.h	nl802154: introduce support for cca settings	2014-12-19 00:19:23 +01:00
p8022.h	…
ping.h	net: Remove iocb argument from sendmsg and recvmsg	2015-03-02 13:06:31 -05:00
pkt_cls.h	net: sched: remove tcf_proto from ematch calls	2014-10-06 18:02:32 -04:00
pkt_sched.h	net: rename vlan_tx_* helpers since "tx" is misleading there	2015-01-13 17:51:08 -05:00
protocol.h	net: Eliminate no_check from protosw	2014-05-23 16:28:53 -04:00
psnap.h	…
raw.h	…
rawv6.h	…
red.h	reciprocal_divide: update/correction of the algorithm	2014-01-21 23:17:20 -08:00
regulatory.h	cfg80211: allow wiphy specific regdomain management	2014-12-17 11:49:55 +01:00
request_sock.h	inet: fix possible panic in reqsk_queue_unlink()	2015-04-24 11:39:15 -04:00
rose.h	…
route.h	ipv4: per cpu uncached list	2015-01-15 18:26:16 -05:00
rtnetlink.h	rtnetlink: Mark name argument of rtnl_create_link() const	2015-04-10 12:42:40 -07:00
sch_generic.h	net_sched: destroy proto tp when all filters are gone	2015-03-09 15:35:55 -04:00
scm.h	…
secure_seq.h	inetpeer: get rid of ip_id_count	2014-06-02 11:00:41 -07:00
slhc_vj.h	…
snmp.h	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
sock.h	Merge branch 'iocb' into for-davem	2015-04-09 00:01:38 -04:00
stp.h	…
switchdev.h	switchdev: kernel-doc cleanup on swithdev ops	2015-03-20 21:36:53 -04:00
tcp.h	tcp: prepare CC get_info() access from getsockopt()	2015-04-29 17:10:38 -04:00
tcp_memcontrol.h	…
tcp_states.h	inet: add TCP_NEW_SYN_RECV state	2015-03-12 22:58:12 -04:00
timewait_sock.h	…
transp_v6.h	ipv6: make IPV6_RECVPKTINFO work for ipv4 datagrams	2014-01-19 19:53:18 -08:00
tso.h	net: Add a software TSO helper API	2014-05-22 14:57:15 -04:00
udp.h	net: Remove iocb argument from sendmsg and recvmsg	2015-03-02 13:06:31 -05:00
udp_tunnel.h	udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb().	2015-04-07 15:29:08 -04:00
udplite.h	net: switch memcpy_fromiovec()/memcpy_fromiovecend() users to copy_from_iter()	2015-02-04 01:34:15 -05:00
vsock_addr.h	…
vxlan.h	udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb().	2015-04-07 15:29:08 -04:00
wext.h	…
wimax.h	net: treewide: Fix typo found in DocBook/networking.xml	2014-09-05 17:35:28 -07:00
x25.h	…
x25device.h	…
xfrm.h	netfilter: Pass socket pointer down through okfn().	2015-04-07 15:25:55 -04:00