Eric Dumazet 5f3e2bf008 tcp: add tcp_min_snd_mss sysctl ... Some TCP peers announce a very small MSS option in their SYN and/or SYN/ACK messages. This forces the stack to send packets with a very high network/cpu overhead. Linux has enforced a minimal value of 48. Since this value includes the size of TCP options, and that the options can consume up to 40 bytes, this means that each segment can include only 8 bytes of payload. In some cases, it can be useful to increase the minimal value to a saner value. We still let the default to 48 (TCP_MIN_SND_MSS), for compatibility reasons. Note that TCP_MAXSEG socket option enforces a minimal value of (TCP_MIN_MSS). David Miller increased this minimal value in commit c39508d6f1 ("tcp: Make TCP_MAXSEG minimum more correct.") from 64 to 88. We might in the future merge TCP_MIN_SND_MSS and TCP_MIN_MSS. CVE-2019-11479 -- tcp mss hardcoded to 48 Signed-off-by: Eric Dumazet <edumazet@google.com> Suggested-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2019-06-15 18:47:31 -07:00
..
caif	…
device_drivers	Documentation: net: move device drivers docs to a submenu	2019-05-22 12:18:20 -07:00
dsa	Documentation: net: dsa: sja1105: Add info about supported traffic modes	2019-05-05 21:52:42 -07:00
mac80211_hwsim	…
6lowpan.txt	docs: networking: fix minor typos in various documentation files	2018-06-04 17:21:28 -04:00
6pack.txt	…
PLIP.txt	…
af_xdp.rst	Documentation/networking: fix af_xdp.rst Sphinx warnings	2019-05-21 16:19:49 +02:00
alias.rst	docs: networking: Convert alias.txt to rst	2018-07-18 15:28:27 -07:00
altera_tse.txt	…
arcnet-hardware.txt	…
arcnet.txt	…
atm.txt	…
ax25.txt	…
batman-adv.rst	batman-adv: Drop documentation about sysfs files	2019-03-25 09:31:35 +01:00
baycom.txt	…
bonding.txt	bonding: Fix a typo in bonding.txt	2018-07-16 13:32:12 -07:00
bridge.rst	docs: networking: Convert bridge.txt to rst	2018-07-18 15:28:27 -07:00
can.rst	docs: can.rst: fix a footnote reference	2018-06-15 12:48:59 -03:00
can_ucan_protocol.rst	can: ucan: add driver for Theobroma Systems UCAN devices	2018-07-27 10:40:16 +02:00
cdc_mbim.txt	…
checksum-offloads.rst	doc: networking: shorten the main title in offloads documents	2019-01-07 15:27:51 -07:00
conf.py	…
cops.txt	…
cxacru-cf.py	…
cxacru.txt	…
dccp.txt	…
dctcp.txt	…
decnet.txt	Documentation: decnet: remove reference to CONFIG_DECNET_ROUTE_FWMARK	2019-04-21 11:25:11 -07:00
defza.txt	FDDI: defza: Add support for DEC FDDIcontroller 700 TURBOchannel adapter	2018-10-15 21:46:06 -07:00
devlink-health.txt	devlink: Add Documentation/networking/devlink-health.txt	2019-02-07 10:34:29 -08:00
devlink-info-versions.rst	Documentation: networking: devlink-info-versions: Add fw.psid	2019-04-08 16:28:01 -07:00
devlink-params-bnxt.txt	devlink: Add Documentation/networking/devlink-params-bnxt.txt	2018-10-04 13:49:43 -07:00
devlink-params-mlxsw.txt	mlxsw: spectrum: add "acl_region_rehash_interval" devlink param	2019-02-08 15:02:50 -08:00
devlink-params.txt	devlink: Add 'fw_load_policy' generic parameter	2018-12-03 13:55:43 -08:00
dns_resolver.txt	…
driver.txt	…
eql.txt	…
failover.rst	net: Introduce generic failover module	2018-05-28 22:59:54 -04:00
fib_trie.txt	…
filter.txt	docs/bpf: minor casing/punctuation fixes	2019-03-02 00:40:04 +01:00
fore200e.txt	…
framerelay.txt	…
gen_stats.txt	…
generic-hdlc.txt	…
generic_netlink.txt	…
gtp.txt	docs: networking: fix minor typos in various documentation files	2018-06-04 17:21:28 -04:00
hinic.txt	…
ieee802154.rst	doc: net: ieee802154: introduce IEEE 802.15.4 subsystem doc in rst style	2019-03-01 17:03:00 -08:00
ila.txt	docs: networking: fix minor typos in various documentation files	2018-06-04 17:21:28 -04:00
index.rst	Documentation: add TLS offload documentation	2019-05-22 12:18:20 -07:00
ip-sysctl.txt	tcp: add tcp_min_snd_mss sysctl	2019-06-15 18:47:31 -07:00
ip_dynaddr.txt	…
ipddp.txt	…
iphase.txt	…
ipsec.txt	docs: networking: fix minor typos in various documentation files	2018-06-04 17:21:28 -04:00
ipv6.txt	…
ipvlan.txt	docs: networking: fix minor typos in various documentation files	2018-06-04 17:21:28 -04:00
ipvs-sysctl.txt	…
kapi.rst	…
kcm.txt	docs: networking: fix minor typos in various documentation files	2018-06-04 17:21:28 -04:00
l2tp.txt	…
lapb-module.txt	…
ltpc.txt	…
mac80211-auth-assoc-deauth.txt	…
mac80211-injection.txt	…
mpls-sysctl.txt	…
msg_zerocopy.rst	doc: fix link to MSG_ZEROCOPY patchset	2019-03-18 09:50:21 -07:00
multiqueue.txt	…
net_dim.txt	Documentation/networking: Add net DIM documentation	2018-03-22 14:50:44 -04:00
net_failover.rst	docs: networking: Fix failover build warnings	2018-07-16 11:23:54 -07:00
netconsole.txt	…
netdev-FAQ.rst	Documentation: fix netdev-FAQ.rst markup warning	2019-05-01 09:12:51 -04:00
netdev-features.txt	docs-networking: fix typo in define	2018-11-21 10:30:30 -08:00
netdevices.txt	…
netfilter-sysctl.txt	…
netif-msg.txt	…
nf_conntrack-sysctl.txt	netfilter: conntrack: register sysctl table for gre	2018-12-21 00:51:25 +01:00
nf_flowtable.txt	netfilter: nf_flowtable: remove duplicated transition in diagram	2019-03-19 15:02:52 +01:00
nfc.txt	…
openvswitch.txt	…
operstates.txt	Documentation: bring operstate documentation up-to-date	2019-02-11 12:38:51 -08:00
packet_mmap.txt	doc: remove out of date links and info from packet mmap	2018-03-16 10:48:52 -04:00
phonet.txt	…
phy.rst	Documentation: net: phy: switch documentation to rst format	2019-01-26 09:16:55 -08:00
pktgen.txt	Documentation/pktgen: Clearify how-to use pktgen samples	2018-01-24 15:03:36 -05:00
ppp_generic.txt	ppp: remove the PPPIOCDETACH ioctl	2018-05-24 22:55:07 -04:00
proc_net_tcp.txt	…
radiotap-headers.txt	…
ray_cs.txt	…
rds.txt	linux-next: DOC: RDS: Fix a typo in rds.txt	2019-06-12 09:56:29 -07:00
regulatory.txt	…
rxrpc.txt	rxrpc: Allow the kernel to mark a call as being non-interruptible	2019-05-16 16:25:20 +01:00
scaling.rst	doc: networking: integrate scaling document into doc tree	2019-01-20 19:10:49 -07:00
sctp.txt	…
secid.txt	…
seg6-sysctl.txt	…
segmentation-offloads.rst	networking: : fix typos in code comments	2019-05-20 20:24:34 -04:00
sfp-phylink.rst	doc: add phylink documentation to the networking book	2019-02-24 12:39:45 -08:00
skfp.txt	…
snmp_counter.rst	networking: fix snmp_counter.rst Doc. Warnings	2019-03-17 19:37:08 -07:00
strparser.txt	strparser: Corrected typo in documentation.	2018-06-24 16:40:20 +09:00
switchdev.txt	switchdev: Remove unused transaction item queue	2019-03-01 21:35:19 -08:00
tc-actions-env-rules.txt	…
tcp-thin.txt	…
team.txt	…
timestamping.txt	socket: Update timestamping Documentation	2019-02-03 11:17:31 -08:00
tls-offload-layers.svg	Documentation: add TLS offload documentation	2019-05-22 12:18:20 -07:00
tls-offload-reorder-bad.svg	Documentation: add TLS offload documentation	2019-05-22 12:18:20 -07:00
tls-offload-reorder-good.svg	Documentation: add TLS offload documentation	2019-05-22 12:18:20 -07:00
tls-offload.rst	Documentation: add TLS offload documentation	2019-05-22 12:18:20 -07:00
tls.rst	Documentation: add TLS offload documentation	2019-05-22 12:18:20 -07:00
tproxy.txt	netfilter: doc: Add nf_tables part in tproxy.txt	2018-08-16 19:37:07 +02:00
tuntap.txt	…
udplite.txt	…
vrf.txt	net: provide a sysctl raw_l3mdev_accept for raw socket lookup with VRFs	2018-11-07 16:12:38 -08:00
vxlan.txt	…
x25-iface.txt	…
x25.txt	…
xfrm_device.txt	net: switch secpath to use skb extension infrastructure	2018-12-19 11:21:38 -08:00
xfrm_proc.txt	…
xfrm_sync.txt	…
xfrm_sysctl.txt	…
z8530book.rst	…
z8530drv.txt	…