linux/net
Si-Wei Liu 8065a779f1 failover: allow name change on IFF_UP slave interfaces
When a netdev appears through hot plug then gets enslaved by a failover
master that is already up and running, the slave will be opened
right away after getting enslaved. Today there's a race that userspace
(udev) may fail to rename the slave if the kernel (net_failover)
opens the slave earlier than when the userspace rename happens.
Unlike bond or team, the primary slave of failover can't be renamed by
userspace ahead of time, since the kernel initiated auto-enslavement is
unable to, or rather, is never meant to be synchronized with the rename
request from userspace.

As the failover slave interfaces are not designed to be operated
directly by userspace apps: IP configuration, filter rules with
regard to network traffic passing and etc., should all be done on master
interface. In general, userspace apps only care about the
name of master interface, while slave names are less important as long
as admin users can see reliable names that may carry
other information describing the netdev. For e.g., they can infer that
"ens3nsby" is a standby slave of "ens3", while for a
name like "eth0" they can't tell which master it belongs to.

Historically the name of IFF_UP interface can't be changed because
there might be admin script or management software that is already
relying on such behavior and assumes that the slave name can't be
changed once UP. But failover is special: with the in-kernel
auto-enslavement mechanism, the userspace expectation for device
enumeration and bring-up order is already broken. Previously initramfs
and various userspace config tools were modified to bypass failover
slaves because of auto-enslavement and duplicate MAC address. Similarly,
in case that users care about seeing reliable slave name, the new type
of failover slaves needs to be taken care of specifically in userspace
anyway.

It's less risky to lift up the rename restriction on failover slave
which is already UP. Although it's possible this change may potentially
break userspace component (most likely configuration scripts or
management software) that assumes slave name can't be changed while
UP, it's relatively a limited and controllable set among all userspace
components, which can be fixed specifically to listen for the rename
events on failover slaves. Userspace component interacting with slaves
is expected to be changed to operate on failover master interface
instead, as the failover slave is dynamic in nature which may come and
go at any point.  The goal is to make the role of failover slaves less
relevant, and userspace components should only deal with failover master
in the long run.

Fixes: 30c8bd5aa8 ("net: Introduce generic failover module")
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Acked-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-10 22:12:26 -07:00
..
6lowpan 6lowpan: fix debugfs_simple_attr.cocci warnings 2019-01-22 09:51:19 +01:00
9p 9p/net: fix memory leak in p9_client_create 2019-03-13 11:50:04 +01:00
802
8021q vlan: conditional inclusion of FCoE hooks to match netdevice.h and bnx2x 2019-04-04 17:18:34 -07:00
appletalk appletalk: Fix potential NULL pointer dereference in unregister_snap_client 2019-03-15 11:25:48 -07:00
atm net: atm: Add another IS_ENABLED(CONFIG_COMPAT) in atm_dev_ioctl 2019-03-07 10:14:50 -08:00
ax25 ax25: fix possible use-after-free 2019-01-23 11:18:00 -08:00
batman-adv batman-adv: Fix genl notification for throughput_override 2019-03-25 09:31:19 +01:00
bluetooth Bluetooth: Add quirk for reading BD_ADDR from fwnode property 2019-02-26 10:08:26 +01:00
bpf bpf: fix warning about using plain integer as NULL 2019-03-08 21:17:07 +01:00
bpfilter bpfilter: re-add header search paths to tools include to fix build error 2019-02-23 13:34:40 -08:00
bridge net: bridge: always clear mcast matching struct on reports and leaves 2019-04-04 17:52:40 -07:00
caif net: caif: use skb helpers instead of open-coding them 2019-02-17 11:01:17 -08:00
can can: bcm: check timer values before ktime conversion 2019-01-22 11:33:46 +01:00
ceph libceph: fix breakage caused by multipage bvecs 2019-03-25 22:28:07 +01:00
core failover: allow name change on IFF_UP slave interfaces 2019-04-10 22:12:26 -07:00
dcb
dccp dccp: Fix memleak in __feat_register_sp 2019-04-01 18:15:10 -07:00
decnet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-01-29 21:18:54 -08:00
dns_resolver
dsa net: dsa: Implement flow_dissect callback for tag_qca 2019-03-28 16:57:19 -07:00
ethernet net/ethernet: Add parse_protocol header_ops support 2019-02-22 12:55:31 -08:00
hsr net/hsr: fix possible crash in add_timer() 2019-03-07 11:02:08 -08:00
ieee802154 net: remove unused struct inet_frag_queue.fragments field 2019-02-26 08:27:05 -08:00
ife
ipv4 net: ip_gre: fix possible use-after-free in erspan_rcv 2019-04-08 16:16:47 -07:00
ipv6 net: ip6_gre: fix possible use-after-free in ip6erspan_rcv 2019-04-08 16:16:47 -07:00
iucv
kcm kcm: switch order of device registration to fix a crash 2019-04-01 14:59:20 -07:00
key af_key: unconditionally clone on broadcast 2019-02-12 10:36:42 +01:00
l2tp l2tp: fix infoleak in l2tp_ip6_recvmsg() 2019-03-13 14:19:35 -07:00
l3mdev l3mdev: add function to retreive upper master 2018-12-03 14:15:26 -08:00
lapb
llc
mac80211 mac80211: Honor SW_CRYPTO_CONTROL for unicast keys in AP VLAN mode 2019-04-09 13:40:32 +02:00
mac802154
mpls mpls: Fix 6PE forwarding 2019-03-19 16:00:22 -07:00
ncsi net: ncsi: fix a missing check for nla_nest_start 2019-03-16 11:44:33 -07:00
netfilter netfilter: nf_tables: add missing ->release_ops() in error path of newrule() 2019-03-20 08:32:58 +01:00
netlabel netlabel: fix out-of-bounds memory accesses 2019-02-27 21:45:24 -08:00
netlink genetlink: Fix a memory leak on error path 2019-03-21 09:29:06 -07:00
netrom netrom: switch to sock timer API 2019-01-27 10:38:04 -08:00
nfc NFC: nci: Add some bounds checking in nci_hci_cmd_received() 2019-04-06 15:05:07 -07:00
nsh
openvswitch openvswitch: fix flow actions reallocation 2019-03-28 17:15:44 -07:00
packet net/packet: Set __GFP_NOWARN upon allocation in alloc_pg_vec 2019-03-20 10:46:50 -07:00
phonet phonet: fix building with clang 2019-02-21 16:23:56 -08:00
psample
qrtr mm: replace all open encodings for NUMA_NO_NODE 2019-03-05 21:07:14 -08:00
rds net: rds: force to destroy connection if t_sock is NULL in rds_tcp_kill_sock(). 2019-03-28 17:17:18 -07:00
rfkill rfkill: gpio: Remove unused include 2018-12-18 13:13:56 +01:00
rose net: rose: fix a possible stack overflow 2019-03-18 16:53:22 -07:00
rxrpc rxrpc: avoid clang -Wuninitialized warning 2019-03-23 21:48:30 -04:00
sched sch_cake: Make sure we can write the IP header before changing DSCP bits 2019-04-04 10:55:59 -07:00
sctp sctp: initialize _pad of sockaddr_in before copying to user memory 2019-04-01 18:08:19 -07:00
smc Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-03-12 13:27:20 -07:00
strparser net: strparser: partially revert "strparser: Call skb_unclone conditionally" 2019-04-10 13:07:02 -07:00
sunrpc SUNRPC: fix uninitialized variable warning 2019-03-26 13:04:32 -07:00
switchdev switchdev: Remove unused transaction item queue 2019-03-01 21:35:19 -08:00
tipc tipc: handle the err returned from cmd header function 2019-03-31 16:45:57 -07:00
tls net/tls: fix build without CONFIG_TLS_DEVICE 2019-04-10 17:23:26 -07:00
unix io_uring-2019-03-06 2019-03-08 14:48:40 -08:00
vmw_vsock vsock/virtio: fix kernel panic from virtio_transport_reset_no_sock 2019-03-08 15:15:44 -08:00
wimax
wireless nl80211: Add NL80211_FLAG_CLEAR_SKB flag for other NL commands 2019-03-29 11:23:09 +01:00
x25 net/x25: reset state in x25_connect() 2019-03-11 15:40:14 -07:00
xdp xsk: fix umem memory leak on cleanup 2019-03-16 01:27:51 +01:00
xfrm xfrm: Fix inbound traffic via XFRM interfaces across network namespaces 2019-02-18 10:58:54 +01:00
Kconfig net: devlink: turn devlink into a built-in 2019-02-26 08:49:05 -08:00
Makefile net: split out functions related to registering inflight socket files 2019-02-28 08:24:23 -07:00
compat.c Merge branch 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-03-05 14:08:26 -08:00
socket.c net: add documentation to socket.c 2019-03-15 15:29:47 -07:00
sysctl_net.c