linux/net
Ido Schimmel 76c03bf8e2 nexthop: Do not flush blackhole nexthops when loopback goes down
As far as user space is concerned, blackhole nexthops do not have a
nexthop device and therefore should not be affected by the
administrative or carrier state of any netdev.

However, when the loopback netdev goes down all the blackhole nexthops
are flushed. This happens because internally the kernel associates
blackhole nexthops with the loopback netdev.

This behavior is both confusing to those not familiar with kernel
internals and also diverges from the legacy API where blackhole IPv4
routes are not flushed when the loopback netdev goes down:

 # ip route add blackhole 198.51.100.0/24
 # ip link set dev lo down
 # ip route show 198.51.100.0/24
 blackhole 198.51.100.0/24

Blackhole IPv6 routes are flushed, but at least user space knows that
they are associated with the loopback netdev:

 # ip -6 route show 2001:db8:1::/64
 blackhole 2001:db8:1::/64 dev lo metric 1024 pref medium

Fix this by only flushing blackhole nexthops when the loopback netdev is
unregistered.

Fixes: ab84be7e54 ("net: Initial nexthop code")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reported-by: Donald Sharp <sharpd@nvidia.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-04 14:04:49 -08:00
..
6lowpan
9p net: 9p: advance iov on empty read 2021-03-03 16:57:59 -08:00
802
8021q Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-01-14 18:34:50 -08:00
appletalk appletalk: Fix skb allocation size in loopback case 2021-02-12 16:40:28 -08:00
atm net: atm: pppoatm: use new API for wakeup tasklet 2021-01-29 18:24:05 -08:00
ax25
batman-adv This feature/cleanup patchset is an updated version of the pull request 2021-02-08 11:32:40 -08:00
bluetooth Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kern 2021-02-11 14:59:01 -08:00
bpf Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-01-20 12:16:11 -08:00
bpfilter net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
bridge bridge: mrp: Update br_mrp to use new return values of br_mrp_switchdev 2021-02-16 14:47:46 -08:00
caif net: caif: Use netif_rx_any_context(). 2021-02-15 13:21:48 -08:00
can net: introduce CAN specific pointer in the struct net_device 2021-02-24 14:32:15 -08:00
ceph libceph: remove osdtimeout option entirely 2021-02-16 12:09:52 +01:00
core rtnetlink: using dev_base_seq from target net 2021-03-03 16:59:17 -08:00
dcb net: dcb: use obj-$(CONFIG_DCB) form in net/Makefile 2021-01-27 17:03:52 -08:00
dccp dccp: Return the correct errno code 2021-02-06 11:15:28 -08:00
decnet net: decnet: fix netdev refcount leaking on error path 2021-01-27 17:33:46 -08:00
dns_resolver net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
dsa net: dsa: tag_mtk: fix 802.1ad VLAN egress 2021-03-01 15:29:43 -08:00
ethernet
ethtool ethtool: fix the check logic of at least one channel for RX/TX 2021-02-28 11:49:07 -08:00
hsr net: hsr: add support for EntryForgetTime 2021-02-25 09:41:51 -08:00
ieee802154
ife net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
ipv4 nexthop: Do not flush blackhole nexthops when loopback goes down 2021-03-04 14:04:49 -08:00
ipv6 net: always use icmp{,v6}_ndo_send from ndo_start_xmit 2021-03-01 13:11:35 -08:00
iucv net/af_iucv: build SG skbs for TRANS_HIPER sockets 2021-01-28 20:36:22 -08:00
kcm net: group skb_shinfo zerocopy related bits together. 2021-01-07 16:08:37 -08:00
key af_key: relax availability checks for skb size calculation 2021-01-04 10:05:50 +01:00
l2tp net: l2tp: reduce log level of messages in receive path, add counter instead 2021-03-03 16:55:02 -08:00
l3mdev net: l3mdev: use obj-$(CONFIG_NET_L3_MASTER_DEV) form in net/Makefile 2021-01-27 17:03:52 -08:00
lapb net: lapb: Copy the skb before sending a packet 2021-02-02 08:40:48 -08:00
llc net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
mac80211 cfg80211/mac80211: Support disabling HE mode 2021-02-12 09:33:34 +01:00
mac802154
mpls
mptcp mptcp: do not wakeup listener for MPJ subflows 2021-02-22 18:54:59 -08:00
ncsi net/ncsi: Use real net-device for response handler 2020-12-23 12:22:23 -08:00
netfilter netfilter: nftables: introduce table ownership 2021-02-15 18:17:15 +01:00
netlabel
netlink mptcp: avoid lock_fast usage in accept path 2021-02-12 16:31:46 -08:00
netrom
nfc TTY/Serial driver changes for 5.12-rc1 2021-02-20 21:28:04 -08:00
nsh
openvswitch net: openvswitch: add log message for error case 2021-01-14 16:32:14 -08:00
packet net/packet: Improve the comment about LL header visibility criteria 2021-02-06 14:59:28 -08:00
phonet
psample net: psample: Fix netlink skb length with tunnel info 2021-02-25 09:49:46 -08:00
qrtr net/qrtr: fix __netdev_alloc_skb call 2021-03-01 13:24:03 -08:00
rds net/rds: restrict iovecs length for RDS_CMSG_RDMA_ARGS 2021-02-02 08:44:08 -08:00
rfkill rfkill: add a reason to the HW rfkill state 2020-12-11 12:47:17 +01:00
rose
rxrpc rxrpc: Fix dependency on IPv6 in udp tunnel config 2021-02-12 16:42:05 -08:00
sched net/sched: cls_flower: validate ct_state for invalid and reply flags 2021-02-23 12:23:44 -08:00
sctp net: sctp: trivial: fix typo in comment 2021-03-04 13:48:32 -08:00
smc net/smc: use memcpy instead of snprintf to avoid out of bounds read 2021-01-12 20:22:01 -08:00
strparser
sunrpc Optimization: 2021-02-22 13:29:55 -08:00
switchdev net: bridge: propagate extack through switchdev_port_attr_set 2021-02-14 17:38:11 -08:00
tipc tipc: remove duplicated code in tipc_msg_create 2021-01-27 18:50:07 -08:00
tls net/tls: Select SOCK_RX_QUEUE_MAPPING from TLS_DEVICE 2021-02-11 19:08:06 -08:00
unix af_unix: handle idmapped mounts 2021-01-24 14:27:18 +01:00
vmw_vsock vsock: fix locking in vsock_shutdown() 2021-02-09 15:31:22 -08:00
wireless cfg80211/mac80211: Support disabling HE mode 2021-02-12 09:33:34 +01:00
x25 net: x25: Remove unimplemented X.25-over-LLC code stubs 2020-12-12 17:15:33 -08:00
xdp xsk: Fold xp_assign_dev and __xp_assign_dev 2021-01-25 23:56:33 +01:00
xfrm Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2021-02-09 11:23:41 -08:00
compat.c
devres.c
Kconfig net/sock: Add kernel config SOCK_RX_QUEUE_MAPPING 2021-02-11 19:08:06 -08:00
Makefile net: l3mdev: use obj-$(CONFIG_NET_L3_MASTER_DEV) form in net/Makefile 2021-01-27 17:03:52 -08:00
socket.c idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
sysctl_net.c