android_kernel_oneplus_msm8998/net
Ihar Hrachyshka cac18a2f4b arp: honour gratuitous ARP _replies_
[ Upstream commit 23d268eb240954e6e78f7cfab04f2b1e79f84489 ]

When arp_accept is 1, gratuitous ARPs are supposed to override matching
entries irrespective of whether they arrive during locktime. This was
implemented in commit 56022a8fdd ("ipv4: arp: update neighbour address
when a gratuitous arp is received and arp_accept is set")

There is a glitch in the patch though. RFC 2002, section 4.6, "ARP,
Proxy ARP, and Gratuitous ARP", defines gratuitous ARPs so that they can
be either of Request or Reply type. Those Reply gratuitous ARPs can be
triggered with standard tooling, for example, arping -A option does just
that.

This patch fixes the glitch, making both Request and Reply flavours of
gratuitous ARPs to behave identically.

As per RFC, if gratuitous ARPs are of Reply type, their Target Hardware
Address field should also be set to the link-layer address to which this
cache entry should be updated. The field is present in ARP over Ethernet
but not in IEEE 1394. In this patch, I don't consider any broadcasted
ARP replies as gratuitous if the field is not present, to conform the
standard. It's not clear whether there is such a thing for IEEE 1394 as
a gratuitous ARP reply; until it's cleared up, we will ignore such
broadcasts. Note that they will still update existing ARP cache entries,
assuming they arrive out of locktime time interval.

Signed-off-by: Ihar Hrachyshka <ihrachys@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13 19:50:07 +02:00
..
6lowpan 6lowpan: put mcast compression in an own function 2015-10-21 00:49:25 +02:00
9p net/9p: Switch to wait_event_killable() 2017-11-30 08:37:25 +00:00
802
8021q net/8021q: create device with all possible features in wanted_features 2018-03-22 09:23:21 +01:00
appletalk
atm atm: deal with setting entry before mkip was called 2015-09-17 22:13:32 -07:00
ax25 ax25: Fix segfault after sock connection timeout 2017-02-04 09:45:09 +01:00
batman-adv batman-adv: handle race condition for claims between gateways 2018-03-22 09:23:21 +01:00
bluetooth Bluetooth: Fix missing encryption refresh on Security Request 2018-04-08 11:51:59 +02:00
bridge netfilter: bridge: ebt_among: add more missing match size checks 2018-04-08 11:51:59 +02:00
caif net: caif: Fix a sleep-in-atomic bug in cfpkt_create_pfx 2017-07-05 14:37:14 +02:00
can can: af_can: canfd_rcv(): replace WARN_ONCE by pr_warn_once 2018-01-31 12:06:08 +01:00
ceph libceph: force GFP_NOIO for socket allocations 2017-04-08 09:53:30 +02:00
core neighbour: update neigh timestamps iff update is effective 2018-04-13 19:50:06 +02:00
dcb net/dcb: make dcbnl.c explicitly non-modular 2015-10-09 07:52:27 -07:00
dccp dccp: check sk for closed state in dccp_sendmsg() 2018-03-31 18:12:33 +02:00
decnet dn_getsockoptdecnet: move nf_{get/set}sockopt outside sock lock 2018-02-25 11:03:38 +01:00
dns_resolver KEYS: Fix race between updating and finding a negative key 2017-10-27 10:23:18 +02:00
dsa net: dsa: select NET_SWITCHDEV 2017-11-15 17:13:11 +01:00
ethernet net: introduce device min_header_len 2017-02-18 16:39:27 +01:00
hsr net/hsr: fix a warning message 2015-11-23 14:56:15 -05:00
ieee802154 ieee802154: 6lowpan: fix possible NULL deref in lowpan_device_event() 2018-03-31 18:12:34 +02:00
ipv4 arp: honour gratuitous ARP _replies_ 2018-04-13 19:50:07 +02:00
ipv6 ipv6: avoid dad-failures for addresses with NODAD 2018-04-13 19:50:06 +02:00
ipx ipx: call ipxitf_put() in ioctl error path 2017-05-25 14:30:13 +02:00
irda irda: do not leak initialized list.dev to userspace 2017-08-30 10:19:21 +02:00
iucv net/iucv: Free memory obtained by kzalloc 2018-03-31 18:12:33 +02:00
key af_key: Fix slab-out-of-bounds in pfkey_compile_policy. 2018-04-13 19:50:01 +02:00
l2tp l2tp: do not accept arbitrary sockets 2018-03-31 18:12:33 +02:00
l3mdev net: Add netif_is_l3_slave 2015-10-07 04:27:43 -07:00
lapb
llc net/llc: avoid BUG_ON() in skb_orphan() 2017-02-26 11:07:49 +01:00
mac80211 mac80211: bail out from prep_connection() if a reconfig is ongoing 2018-04-13 19:50:01 +02:00
mac802154 mac802154: llsec: use kzfree 2015-10-21 00:49:24 +02:00
mpls mpls, nospec: Sanitize array index in mpls_label_ok() 2018-03-11 16:19:47 +01:00
netfilter netfilter: x_tables: add and use xt_check_proc_name 2018-04-08 11:51:59 +02:00
netlabel netlabel: add address family checks to netlbl_{sock,req}_delattr() 2016-08-20 18:09:22 +02:00
netlink netlink: avoid a double skb free in genlmsg_mcast() 2018-03-31 18:12:33 +02:00
netrom
nfc NFC: fix device-allocation error return 2017-11-30 08:37:23 +00:00
openvswitch openvswitch: Delete conntrack entry clashing with an expectation. 2018-03-24 10:58:43 +01:00
packet net/packet: fix a race in packet_bind() and packet_notifier() 2017-12-16 10:33:56 +01:00
phonet phonet: properly unshare skbs in phonet_rcv() 2016-01-31 11:29:00 -08:00
rds RDS: null pointer dereference in rds_atomic_free_op 2018-01-17 09:35:29 +01:00
rfkill rfkill: fix rfkill_fop_read wait_event usage 2016-03-03 15:07:26 -08:00
rose
rxrpc rxrpc: Fix several cases where a padded len isn't checked in ticket decode 2017-06-29 12:48:52 +02:00
sched sched: act_csum: don't mangle TCP and UDP GSO packets 2018-03-22 09:23:22 +01:00
sctp fixup: sctp: verify size of a new chunk in _sctp_make_chunk() 2018-03-18 11:17:54 +01:00
sunrpc SUNRPC: Allow connect to return EHOSTUNREACH 2018-02-03 17:04:28 +01:00
switchdev switchdev: pass pointer to fib_info instead of copy 2016-06-24 10:18:16 -07:00
tipc tipc: fix memory leak in tipc_accept_from_sock() 2017-12-16 10:33:56 +01:00
unix net/unix: don't show information about sockets from other namespaces 2017-11-18 11:11:06 +01:00
vmw_vsock vsock: use new wait API for vsock_stream_sendmsg() 2017-11-30 08:37:19 +00:00
wimax net:wimax: Fix doucble word "the the" in networking.xml 2015-08-09 22:43:52 -07:00
wireless nl80211: Sanitize array index in parse_txq_params 2018-02-25 11:03:53 +01:00
x25 net: fix a kernel infoleak in x25 module 2016-05-18 17:06:43 -07:00
xfrm xfrm: Refuse to insert 32 bit userspace socket policies on 64 bit systems 2018-04-08 11:51:59 +02:00
compat.c audit: log 32-bit socketcalls 2017-10-08 10:14:18 +02:00
Kconfig Make DST_CACHE a silent config option 2018-02-25 11:03:37 +01:00
Makefile net: Introduce L3 Master device abstraction 2015-09-29 20:40:32 -07:00
socket.c bpf: introduce BPF_JIT_ALWAYS_ON config 2018-02-03 17:04:24 +01:00
sysctl_net.c net: Use ns_capable_noaudit() when determining net sysctl permissions 2016-09-15 08:27:50 +02:00