linux-stable/net
Eric Dumazet 84b114b984 tcp: randomize timestamps on syncookies
Whole point of randomization was to hide server uptime, but an attacker
can simply start a syn flood and TCP generates 'old style' timestamps,
directly revealing server jiffies value.

Also, TSval sent by the server to a particular remote address vary
depending on syncookies being sent or not, potentially triggering PAWS
drops for innocent clients.

Lets implement proper randomization, including for SYNcookies.

Also we do not need to export sysctl_tcp_timestamps, since it is not
used from a module.

In v2, I added Florian feedback and contribution, adding tsoff to
tcp_get_cookie_sock().

v3 removed one unused variable in tcp_v4_connect() as Florian spotted.

Fixes: 95a22caee3 ("tcp: randomize tcp timestamp offsets for each connection")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Tested-by: Florian Westphal <fw@strlen.de>
Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-05 12:00:11 -04:00
..
6lowpan 6lowpan: Don't set IFF_NO_QUEUE 2017-04-12 22:02:40 +02:00
9p xen: fixes and featrues for 4.12 2017-05-04 11:37:09 -07:00
802
8021q netlink: pass extended ACK struct to parsing functions 2017-04-13 13:58:22 -04:00
appletalk lib/vsprintf.c: remove %Z support 2017-02-27 18:43:47 -08:00
atm neighbour: fix nlmsg_pid in notifications 2017-03-22 10:48:49 -07:00
ax25 net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
batman-adv This feature/cleanup patchset includes the following patches: 2017-04-06 14:37:50 -07:00
bluetooth Bluetooth: Add selftest for ECDH key generation 2017-04-30 16:52:43 +03:00
bpf bpf: Align packet data properly in program testing framework. 2017-05-02 11:46:28 -04:00
bridge bridge: netlink: account for IFLA_BRPORT_{B, M}CAST_FLOOD size and policy 2017-05-05 11:21:03 -04:00
caif sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h> 2017-03-02 08:42:29 +01:00
can can: fix CAN BCM build with CONFIG_PROC_FS disabled 2017-04-27 09:34:13 +02:00
ceph libceph: force GFP_NOIO for socket allocations 2017-03-23 12:03:36 +01:00
core tcp: randomize timestamps on syncookies 2017-05-05 12:00:11 -04:00
dcb net: rtnetlink: plumb extended ack to doit function 2017-04-17 15:35:38 -04:00
dccp dccp: fix memory leak during tear-down of unsuccessful connection request 2017-03-13 22:00:42 -07:00
decnet Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2017-05-01 10:47:53 -04:00
dns_resolver Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-03-03 10:16:38 -08:00
dsa net: dsa: Remove redundant NULL dst check 2017-04-21 10:41:24 -04:00
ethernet
hsr netlink: extended ACK reporting 2017-04-13 13:58:20 -04:00
ieee802154 netlink: pass extended ACK struct where available 2017-04-13 13:58:22 -04:00
ife
ipv4 tcp: randomize timestamps on syncookies 2017-05-05 12:00:11 -04:00
ipv6 tcp: randomize timestamps on syncookies 2017-05-05 12:00:11 -04:00
ipx ipx: call ipxitf_put() in ioctl error path 2017-05-02 15:34:53 -04:00
irda net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
iucv net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
kcm kcm: remove a useless copy_from_user() 2017-04-17 13:28:48 -04:00
key Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-21 20:23:53 -07:00
l2tp l2tp: remove useless device duplication test in l2tp_eth_create() 2017-04-27 16:32:13 -04:00
l3mdev
lapb
llc net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
mac80211 cfg80211: add request id to cfg80211_sched_scan_*() api 2017-04-28 14:51:43 +02:00
mac802154 drivers: add explicit interrupt.h includes 2017-03-30 11:05:34 -07:00
mpls net: rtnetlink: plumb extended ack to doit function 2017-04-17 15:35:38 -04:00
ncsi
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-05-04 12:26:43 -07:00
netlabel netlink: pass extended ACK struct to parsing functions 2017-04-13 13:58:22 -04:00
netlink netlink: pass extended ACK struct where available 2017-04-13 13:58:22 -04:00
netrom net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
nfc NFC 4.12 pull request 2017-04-21 15:29:40 -04:00
openvswitch Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2017-05-03 10:11:26 -04:00
packet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-26 22:39:08 -04:00
phonet net: rtnetlink: plumb extended ack to doit function 2017-04-17 15:35:38 -04:00
psample
qrtr Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-21 20:23:53 -07:00
rds Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
rfkill
rose net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
rxrpc rxrpc: Trace client call connection 2017-04-06 11:10:41 +01:00
sched net/sched: remove redundant null check on head 2017-05-04 11:01:30 -04:00
sctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
smc IB/core: Define 'ib' and 'roce' rdma_ah_attr types 2017-05-01 14:32:43 -04:00
strparser strparser: destroy workqueue on module exit 2017-03-03 20:43:26 -08:00
sunrpc The restriction of NFSv4 to TCP went overboard and also broke the 2017-04-01 10:43:37 -07:00
switchdev netlink: pass extended ACK struct to parsing functions 2017-04-13 13:58:22 -04:00
tipc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
unix af_unix: Use designated initializers 2017-04-06 12:43:04 -07:00
vmw_vsock VSOCK: Add virtio vsock vsockmon hooks 2017-04-24 12:35:56 -04:00
wimax
wireless cfg80211: add request id to cfg80211_sched_scan_*() api 2017-04-28 14:51:43 +02:00
x25 net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
compat.c
Kconfig
Makefile bpf: introduce BPF_PROG_TEST_RUN command 2017-04-01 12:45:57 -07:00
socket.c l2tp: device MTU setup, tunnel socket needs a lock 2017-04-17 13:01:48 -04:00
sysctl_net.c