linux/net
Florian Westphal ce6dd23329 dctcp: avoid bogus doubling of cwnd after loss
If a congestion control module doesn't provide .undo_cwnd function,
tcp_undo_cwnd_reduction() will set cwnd to

   tp->snd_cwnd = max(tp->snd_cwnd, tp->snd_ssthresh << 1);

... which makes sense for reno (it sets ssthresh to half the current cwnd),
but it makes no sense for dctcp, which sets ssthresh based on the current
congestion estimate.

This can cause severe growth of cwnd (eventually overflowing u32).

Fix this by saving last cwnd on loss and restore cwnd based on that,
similar to cubic and other algorithms.

Fixes: e3118e8359 ("net: tcp: add DCTCP congestion control algorithm")
Cc: Lawrence Brakmo <brakmo@fb.com>
Cc: Andrew Shewmaker <agshew@gmail.com>
Cc: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-31 15:16:28 -04:00
..
6lowpan 6lowpan: ndisc: no overreact if no short address is available 2016-09-19 20:19:34 +02:00
9p IB/core: add support to create a unsafe global rkey to ib_create_pd 2016-09-23 13:47:44 -04:00
802
8021q net: add recursion limit to GRO 2016-10-20 14:32:22 -04:00
appletalk appletalk: use IS_ENABLED() instead of checking for built-in or module 2016-09-10 21:19:10 -07:00
atm lec: use IS_ENABLED() instead of checking for built-in or module 2016-09-10 21:19:10 -07:00
ax25
batman-adv batman-adv: fix splat on disabling an interface 2016-10-21 14:47:02 +02:00
bluetooth Bluetooth: Fix append max 11 bytes of name to scan rsp data 2016-10-19 18:42:37 +02:00
bridge bridge: multicast: restore perm router ports on multicast enable 2016-10-18 13:52:13 -04:00
caif
can
ceph mm: replace get_user_pages_unlocked() write/force parameters with gup_flags 2016-10-18 14:13:37 -07:00
core Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-10-29 20:33:20 -07:00
dcb
dccp Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2016-07-29 17:38:46 -07:00
decnet net: fix decnet rtnexthop parsing 2016-07-05 14:08:47 -07:00
dns_resolver
dsa net: dsa: add port fast ageing 2016-09-23 08:38:50 -04:00
ethernet net: add recursion limit to GRO 2016-10-20 14:32:22 -04:00
hsr net/hsr: Remove unused but set variable 2016-10-18 10:28:18 -04:00
ieee802154 ieee802154: 6lowpan: fix intra pan id check 2016-07-08 13:23:12 +02:00
ipv4 dctcp: avoid bogus doubling of cwnd after loss 2016-10-31 15:16:28 -04:00
ipv6 ipv6: add mtu lock check in __ip6_rt_update_pmtu 2016-10-31 14:24:24 -04:00
ipx
irda Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-09-23 06:46:57 -04:00
iucv Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2016-07-29 17:38:46 -07:00
kcm Merge branch 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-07 15:36:58 -07:00
key
l2tp udp: must lock the socket in udp_disconnect() 2016-10-20 14:45:52 -04:00
l3mdev net: ipv6: Remove l3mdev_get_saddr6 2016-09-10 23:12:53 -07:00
lapb
llc llc: switch type to bool as the timeout is only tested versus 0 2016-09-17 10:05:05 -04:00
mac80211 mac80211: move struct aead_req off the stack 2016-10-17 16:14:04 +02:00
mac802154 mac802154: use rate limited warnings for malformed frames 2016-09-19 20:19:34 +02:00
mpls mpls: move mpls_hdr to a common location 2016-10-03 02:00:21 -04:00
ncsi net/ncsi: Improve HNCDSC AEN handler 2016-10-20 11:23:08 -04:00
netfilter netfilter: fix nf_queue handling 2016-10-20 19:59:59 +02:00
netlabel
netlink netlink: do not enter direct reclaim from netlink_dump() 2016-10-06 20:53:13 -04:00
netrom
nfc NFC: digital: Fix RTOX supervisor PDU handling 2016-07-11 02:02:03 +02:00
openvswitch openvswitch: add NETIF_F_HW_VLAN_STAG_TX to internal dev 2016-10-13 10:03:23 -04:00
packet packet: on direct_xmit, limit tso and csum to supported devices 2016-10-29 15:02:15 -04:00
phonet
qrtr
rds rds: debug messages are enabled by default 2016-10-29 15:55:57 -04:00
rfkill
rose rose: limit sk_filter trim to payload 2016-07-13 11:53:40 -07:00
rxrpc rxrpc: Fix checking of error from ip6_route_output() 2016-10-13 08:43:17 +01:00
sched net_sched actions: use nla_parse_nested() 2016-10-29 15:01:01 -04:00
sctp sctp: validate chunk len before actually using it 2016-10-29 12:00:10 -04:00
strparser strparser: Propagate correct error code in strp_recv() 2016-10-12 01:51:49 -04:00
sunrpc NFS client updates for Linux 4.9 2016-10-13 21:28:20 -07:00
switchdev switchdev: Execute bridge ndos only for bridge ports 2016-10-19 10:58:04 -04:00
tipc tipc: fix broadcast link synchronization problem 2016-10-29 17:21:09 -04:00
unix skb_splice_bits(): get rid of callback 2016-10-03 20:40:56 -04:00
vmw_vsock VSOCK: Don't dec ack backlog twice for rejected connections 2016-09-27 07:59:25 -04:00
wimax
wireless cfg80211: process events caused by suspend before suspending 2016-10-26 07:59:52 +02:00
x25 net: x25: remove null checks on arrays calling_ae and called_ae 2016-09-09 18:13:30 -07:00
xfrm proc: Reduce cache miss in xfrm_statistics_seq_show 2016-09-30 01:50:45 -04:00
compat.c
Kconfig strparser: Stream parser for messages 2016-08-17 19:36:23 -04:00
Makefile strparser: Stream parser for messages 2016-08-17 19:36:23 -04:00
socket.c vfs: Remove {get,set,remove}xattr inode operations 2016-10-07 21:48:36 -04:00
sysctl_net.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2016-10-06 09:52:23 -07:00