linux/net
Ido Schimmel f97f4dd8b3 net: ipv4: Fix memory leak in network namespace dismantle
IPv4 routing tables are flushed in two cases:

1. In response to events in the netdev and inetaddr notification chains
2. When a network namespace is being dismantled

In both cases only routes associated with a dead nexthop group are
flushed. However, a nexthop group will only be marked as dead in case it
is populated with actual nexthops using a nexthop device. This is not
the case when the route in question is an error route (e.g.,
'blackhole', 'unreachable').

Therefore, when a network namespace is being dismantled such routes are
not flushed and leaked [1].

To reproduce:
# ip netns add blue
# ip -n blue route add unreachable 192.0.2.0/24
# ip netns del blue

Fix this by not skipping error routes that are not marked with
RTNH_F_DEAD when flushing the routing tables.

To prevent the flushing of such routes in case #1, add a parameter to
fib_table_flush() that indicates if the table is flushed as part of
namespace dismantle or not.

Note that this problem does not exist in IPv6 since error routes are
associated with the loopback device.

[1]
unreferenced object 0xffff888066650338 (size 56):
  comm "ip", pid 1206, jiffies 4294786063 (age 26.235s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 b0 1c 62 61 80 88 ff ff  ..........ba....
    e8 8b a1 64 80 88 ff ff 00 07 00 08 fe 00 00 00  ...d............
  backtrace:
    [<00000000856ed27d>] inet_rtm_newroute+0x129/0x220
    [<00000000fcdfc00a>] rtnetlink_rcv_msg+0x397/0xa20
    [<00000000cb85801a>] netlink_rcv_skb+0x132/0x380
    [<00000000ebc991d2>] netlink_unicast+0x4c0/0x690
    [<0000000014f62875>] netlink_sendmsg+0x929/0xe10
    [<00000000bac9d967>] sock_sendmsg+0xc8/0x110
    [<00000000223e6485>] ___sys_sendmsg+0x77a/0x8f0
    [<000000002e94f880>] __sys_sendmsg+0xf7/0x250
    [<00000000ccb1fa72>] do_syscall_64+0x14d/0x610
    [<00000000ffbe3dae>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
    [<000000003a8b605b>] 0xffffffffffffffff
unreferenced object 0xffff888061621c88 (size 48):
  comm "ip", pid 1206, jiffies 4294786063 (age 26.235s)
  hex dump (first 32 bytes):
    6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
    6b 6b 6b 6b 6b 6b 6b 6b d8 8e 26 5f 80 88 ff ff  kkkkkkkk..&_....
  backtrace:
    [<00000000733609e3>] fib_table_insert+0x978/0x1500
    [<00000000856ed27d>] inet_rtm_newroute+0x129/0x220
    [<00000000fcdfc00a>] rtnetlink_rcv_msg+0x397/0xa20
    [<00000000cb85801a>] netlink_rcv_skb+0x132/0x380
    [<00000000ebc991d2>] netlink_unicast+0x4c0/0x690
    [<0000000014f62875>] netlink_sendmsg+0x929/0xe10
    [<00000000bac9d967>] sock_sendmsg+0xc8/0x110
    [<00000000223e6485>] ___sys_sendmsg+0x77a/0x8f0
    [<000000002e94f880>] __sys_sendmsg+0xf7/0x250
    [<00000000ccb1fa72>] do_syscall_64+0x14d/0x610
    [<00000000ffbe3dae>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
    [<000000003a8b605b>] 0xffffffffffffffff

Fixes: 8cced9eff1 ("[NETNS]: Enable routing configuration in non-initial namespace.")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-15 13:33:44 -08:00
..
6lowpan 6lowpan: convert to DEFINE_SHOW_ATTRIBUTE 2018-12-19 00:28:05 +01:00
9p 9p/net: put a lower bound on msize 2018-12-25 17:07:49 +09:00
802
8021q net: core: dev: Add extack argument to dev_change_flags() 2018-12-06 13:26:07 -08:00
appletalk
atm Revert "net: simplify sock_poll_wait" 2018-10-23 10:57:06 -07:00
ax25 ax25: fix a use-after-free in ax25_fillin_cb() 2018-12-30 14:07:54 -08:00
batman-adv Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
bluetooth Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-12-27 13:53:32 -08:00
bpf Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-12-10 18:00:43 -08:00
bpfilter net: bpfilter: disallow to remove bpfilter module while being used 2019-01-11 18:05:41 -08:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2019-01-15 13:31:46 -08:00
caif Revert "net: simplify sock_poll_wait" 2018-10-23 10:57:06 -07:00
can can: gw: ensure DLC boundaries after CAN frame modification 2019-01-07 05:17:51 -08:00
ceph libceph: allow setting abort_on_full for rbd 2019-01-07 22:47:48 +01:00
core Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-01-16 05:13:36 +12:00
dcb
dccp mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
decnet mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
dns_resolver dns: Allow the dns resolver to retrieve a server set 2018-10-04 09:40:52 -07:00
dsa net: dsa: ksz: Add STP multicast handling 2018-12-16 14:23:33 -08:00
ethernet net: ethernet: provide nvmem_get_mac_address() 2018-12-03 15:40:30 -08:00
hsr
ieee802154 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-12-24 16:19:56 -08:00
ife
ipv4 net: ipv4: Fix memory leak in network namespace dismantle 2019-01-15 13:33:44 -08:00
ipv6 ip6_gre: fix tunnel list corruption for x-netns 2019-01-15 13:33:44 -08:00
iucv iucv: Remove SKB list assumptions. 2018-11-10 16:55:11 -08:00
kcm
key af_key: fix indentation on declaration statement 2018-11-15 18:09:32 +01:00
l2tp ppp: Move PFC decompression to PPP generic layer 2018-12-20 16:49:30 -08:00
l3mdev l3mdev: add function to retreive upper master 2018-12-03 14:15:26 -08:00
lapb
llc llc: do not use sk_eat_skb() 2018-10-22 19:59:20 -07:00
mac80211 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-12-27 13:53:32 -08:00
mac802154 mac802154: Remove VLA usage of skcipher 2018-09-28 12:46:07 +08:00
mpls net/mpls: Handle kernel side filtering of route dumps 2018-10-16 00:14:07 -07:00
ncsi net/ncsi: Add NCSI Mellanox OEM command 2018-11-27 16:37:20 -08:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2019-01-15 13:31:46 -08:00
netlabel
netlink net: netlink: rename NETLINK_DUMP_STRICT_CHK -> NETLINK_GET_STRICT_CHK 2018-12-14 11:44:31 -08:00
netrom netrom: fix locking in nr_find_socket() 2018-12-30 20:24:16 -08:00
nfc net: Revert recent Spectre-v1 patches. 2018-12-23 16:01:35 -08:00
nsh
openvswitch openvswitch: Fix IPv6 later frags parsing 2019-01-04 13:00:02 -08:00
packet packet: Do not leak dev refcounts on error exit 2019-01-08 21:41:40 -05:00
phonet net: Revert recent Spectre-v1 patches. 2018-12-23 16:01:35 -08:00
psample
qrtr
rds rds: use DIV_ROUND_UP instead of ceil 2019-01-07 07:22:36 -08:00
rfkill rfkill: gpio: Remove unused include 2018-12-18 13:13:56 +01:00
rose
rxrpc rxrpc: Fix life check 2018-11-15 11:35:40 -08:00
sched Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-12-27 13:04:52 -08:00
sctp mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
smc smc: move unhash as early as possible in smc_release() 2019-01-07 14:40:27 -05:00
strparser bpf, sockmap: convert to generic sk_msg interface 2018-10-15 12:23:19 -07:00
sunrpc Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
switchdev net: switchdev: Add extack to switchdev_handle_port_obj_add() callback 2018-12-12 16:34:22 -08:00
tipc tipc: fix memory leak in tipc_nl_compat_publ_dump 2019-01-07 11:42:08 -05:00
tls Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-12-21 15:06:20 -08:00
unix Revert "net: simplify sock_poll_wait" 2018-10-23 10:57:06 -07:00
vmw_vsock VSOCK: Send reset control packet when socket is partially bound 2018-12-18 11:53:42 -08:00
wimax
wireless Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-12-27 13:53:32 -08:00
x25 net/x25: handle call collisions 2018-11-29 14:25:36 -08:00
xdp xsk: simplify AF_XDP socket teardown 2018-12-19 21:45:17 +01:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-12-20 11:53:36 -08:00
compat.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
Kconfig net: convert bridge_nf to use skb extension infrastructure 2018-12-19 11:21:37 -08:00
Makefile
socket.c y2038: more syscalls and cleanups 2018-12-28 12:45:04 -08:00
sysctl_net.c