android_kernel_samsung_msm8226/Documentation
Eric Dumazet e2f9e38480 tcp: add tcp_min_snd_mss sysctl
commit 5f3e2bf008c2221478101ee72f5cb4654b9fc363 upstream.

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>
[Salvatore Bonaccorso: Backport for context changes in 4.9.168]
[bwh: Backported to 3.16: Make the sysctl global, consistent with
 net.ipv4.tcp_base_mss]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
Change-Id: I880c05860586008d00b3de990400536b367459b3
2020-01-06 08:40:44 +01:00
..
ABI netfilter: remove ip_queue support 2020-01-06 08:40:30 +01:00
accounting
acpi
aoe
arm scm-mpu: Add additional memory protection options 2015-05-14 16:38:24 +05:30
ata ata: ahci: MSM AHCI controller driver 2013-04-02 10:30:40 +05:30
auxdisplay
backlight
blackfin
block
blockdev
cdrom
cgroups Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0 2019-08-06 11:41:21 +02:00
connector
console
cpu-freq cpufreq: interactive: allow arbitrary speed / delay mappings 2013-11-20 16:37:37 -08:00
cpuidle cpuidle: make a single register function for all 2013-11-26 11:26:45 -07:00
cris
crypto
development-process
device-mapper Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
devicetree BACKPORT: ARM: dts: msm: Mount the system partition during early init 2020-01-06 08:39:53 +01:00
DocBook
driver-model pinctrl: implement devm_pinctrl_get()/put() 2013-06-14 13:33:55 -07:00
dvb Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
early-userspace
EDID
fault-injection
fb
filesystems Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0 2019-08-06 11:41:21 +02:00
firmware_class
frv
hid HID: uhid: add documentation 2013-03-05 15:10:45 -08:00
hwmon Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
i2c Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
i2o
ia64
ide
infiniband
input Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0 2019-08-06 11:41:21 +02:00
ioctl
isdn
ja_JP Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
kbuild
kdump
ko_KR
laptops
leds
m68k
make
mips
misc-devices
mmc
mn10300
mtd
namespaces
netlabel
networking tcp: add tcp_min_snd_mss sysctl 2020-01-06 08:40:44 +01:00
nfc
parisc
PCI
pcmcia
power Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0 2019-08-06 11:41:21 +02:00
powerpc
pps
prctl
pti
ptp
rapidio
RCU
s390
scheduler
scsi
security
serial
sh
sound Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
sparc
spi
sysctl Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
target
telephony
thermal
timers time: Remove CONFIG_TIMER_STATS 2019-08-06 12:26:30 +02:00
trace Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0 2019-08-06 11:41:21 +02:00
usb USB: ice40-hcd: Add ICE40 FPGA based SPI to Inter-Chip USB host driver 2014-03-12 10:46:11 +05:30
vDSO
video4linux
virtual
vm mm: Backport ZRAM/ZSMALLOC from Google kernel 2019-08-06 08:17:38 +02:00
w1
watchdog
wimax
x86 Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
zh_CN Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
.gitignore
00-INDEX Documentation: Add documentation for the MIPI-BIF framework 2013-03-26 14:03:02 -07:00
android.txt
applying-patches.txt
atomic_ops.txt
bad_memory.txt
basic_profiling.txt
bif-framework.txt bif: bif-core: add BIF NVM object writing support 2013-10-14 10:15:17 -07:00
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt
Changes
circular-buffers.txt
clk.txt
coccinelle.txt
CodingStyle
cpu-hotplug.txt
cpu-load.txt
cputopology.txt
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt
digsig.txt
DMA-API-HOWTO.txt
DMA-API.txt
DMA-attributes.txt common: DMA-mapping: add DMA_ATTR_SKIP_CPU_SYNC attribute 2014-08-18 10:34:41 -07:00
dma-buf-sharing.txt
DMA-ISA-LPC.txt
dmaengine.txt
dontdiff
dynamic-debug-howto.txt
edac.txt
eisa.txt
email-clients.txt
feature-removal-schedule.txt netfilter: remove xt_NOTRACK 2020-01-06 08:40:34 +01:00
flexible-arrays.txt
futex-requeue-pi.txt
gcov.txt
genlock.txt
gpio.txt gpiolib: provide provision to register pin ranges 2013-06-14 13:34:03 -07:00
highuid.txt
HOWTO Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
hw_random.txt
hwspinlock.txt
init.txt
initrd.txt
Intel-IOMMU.txt
intel_txt.txt
io-mapping.txt
io_ordering.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt mm: larger stack guard gap, between vmas 2019-08-06 12:26:29 +02:00
kmemcheck.txt
kmemleak.txt
kobject.txt
kprobes.txt
kref.txt
ldm.txt
local_ops.txt
lockdep-design.txt
lockstat.txt
lockup-watchdogs.txt
logo.gif
logo.txt
lzo.txt Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
magic-number.txt
Makefile
ManagementStyle
mca.txt
md.txt
media-framework.txt
memory-barriers.txt
memory-hotplug.txt
memory.txt
mono.txt
mutex-design.txt
nommu-mmap.txt
numastat.txt
oops-tracing.txt
padata.txt
parport-lowlevel.txt
parport.txt
pi-futex.txt
pinctrl.txt Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
pnp.txt
preempt-locking.txt
printk-formats.txt lib: vsprintf: Add %pa format specifier for phys_addr_t types 2013-03-04 19:30:49 -08:00
prio_tree.txt
ramoops.txt
rbtree.txt
remoteproc.txt
rfkill.txt
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
SM501.txt
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt Merge tag 'v3.4.113' into lineage-16.0 2019-08-05 14:20:47 +02:00
static-keys.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches
svga.txt
sync.txt Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0 2019-08-06 11:41:21 +02:00
sysfs-rules.txt
sysrq.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
volatile-considered-harmful.txt
workqueue.txt workqueue: reimplement WQ_HIGHPRI using a separate worker_pool 2013-05-10 11:18:09 -07:00
xz.txt
zorro.txt