linux/net
David Ahern e434863718 net: vrf: Fix crash when IPv6 is disabled at boot time
Frank Kellermann reported a kernel crash with 4.5.0 when IPv6 is
disabled at boot using the kernel option ipv6.disable=1. Using
current net-next with the boot option:

$ ip link add red type vrf table 1001

Generates:
[12210.919584] BUG: unable to handle kernel NULL pointer dereference at 0000000000000748
[12210.921341] IP: [<ffffffff814b30e3>] fib6_get_table+0x2c/0x5a
[12210.922537] PGD b79e3067 PUD bb32b067 PMD 0
[12210.923479] Oops: 0000 [#1] SMP
[12210.924001] Modules linked in: ipvlan 8021q garp mrp stp llc
[12210.925130] CPU: 3 PID: 1177 Comm: ip Not tainted 4.7.0-rc1+ #235
[12210.926168] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[12210.928065] task: ffff8800b9ac4640 ti: ffff8800bacac000 task.ti: ffff8800bacac000
[12210.929328] RIP: 0010:[<ffffffff814b30e3>]  [<ffffffff814b30e3>] fib6_get_table+0x2c/0x5a
[12210.930697] RSP: 0018:ffff8800bacaf888  EFLAGS: 00010202
[12210.931563] RAX: 0000000000000748 RBX: ffffffff81a9e280 RCX: ffff8800b9ac4e28
[12210.932688] RDX: 00000000000000e9 RSI: 0000000000000002 RDI: 0000000000000286
[12210.933820] RBP: ffff8800bacaf898 R08: ffff8800b9ac4df0 R09: 000000000052001b
[12210.934941] R10: 00000000657c0000 R11: 000000000000c649 R12: 00000000000003e9
[12210.936032] R13: 00000000000003e9 R14: ffff8800bace7800 R15: ffff8800bb3ec000
[12210.937103] FS:  00007faa1766c700(0000) GS:ffff88013ac00000(0000) knlGS:0000000000000000
[12210.938321] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[12210.939166] CR2: 0000000000000748 CR3: 00000000b79d6000 CR4: 00000000000406e0
[12210.940278] Stack:
[12210.940603]  ffff8800bb3ec000 ffffffff81a9e280 ffff8800bacaf8c8 ffffffff814b3135
[12210.941818]  ffff8800bb3ec000 ffffffff81a9e280 ffffffff81a9e280 ffff8800bace7800
[12210.943040]  ffff8800bacaf8f0 ffffffff81397c88 ffff8800bb3ec000 ffffffff81a9e280
[12210.944288] Call Trace:
[12210.944688]  [<ffffffff814b3135>] fib6_new_table+0x24/0x8a
[12210.945516]  [<ffffffff81397c88>] vrf_dev_init+0xd4/0x162
[12210.946328]  [<ffffffff814091e1>] register_netdevice+0x100/0x396
[12210.947209]  [<ffffffff8139823d>] vrf_newlink+0x40/0xb3
[12210.948001]  [<ffffffff814187f0>] rtnl_newlink+0x5d3/0x6d5
...

The problem above is due to the fact that the fib hash table is not
allocated when IPv6 is disabled at boot.

As for the VRF driver it should not do any IPv6 initializations if IPv6
is disabled, so it needs to know if IPv6 is disabled at boot. The disable
parameter is private to the IPv6 module, so provide an accessor for
modules to determine if IPv6 was disabled at boot time.

Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-09 23:34:42 -07:00
..
6lowpan
9p remove lots of IS_ERR_VALUE abuses 2016-05-27 15:26:11 -07:00
802
8021q vlan: Propagate MAC address to VLANs 2016-05-31 11:56:48 -07:00
appletalk
atm net/atm: sk_err_soft must be positive 2016-05-23 13:51:10 -07:00
ax25
batman-adv batman-adv: initialize ELP orig address on secondary interfaces 2016-05-18 11:49:44 +08:00
bluetooth net: add netdev_lockdep_set_classes() helper 2016-06-09 13:28:37 -07:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-05-09 15:59:24 -04:00
caif
can
ceph libceph: make ceph_osdc_wait_request() uninterruptible 2016-05-26 01:15:40 +02:00
core net: Add l3mdev rule 2016-06-08 11:36:02 -07:00
dcb
dccp dccp: do not assume DCCP code is non preemptible 2016-05-02 17:02:25 -04:00
decnet
dns_resolver
dsa net: dsa: Initialize CPU port ethtool ops per tree 2016-06-08 11:23:42 -07:00
ethernet
hsr net/hsr: Use setup_timer and mod_timer. 2016-05-16 14:00:43 -04:00
ieee802154 net: add netdev_lockdep_set_classes() helper 2016-06-09 13:28:37 -07:00
ipv4 net: Add l3mdev rule 2016-06-08 11:36:02 -07:00
ipv6 net: vrf: Fix crash when IPv6 is disabled at boot time 2016-06-09 23:34:42 -07:00
ipx
irda TTY and Serial driver update for 4.7-rc1 2016-05-20 20:57:27 -07:00
iucv
kcm kcm: fix a signedness in kcm_splice_read() 2016-05-19 11:26:51 -07:00
key
l2tp net: add netdev_lockdep_set_classes() helper 2016-06-09 13:28:37 -07:00
l3mdev net: Add l3mdev rule 2016-06-08 11:36:02 -07:00
lapb net/lapb: tuse %*ph to dump buffers 2016-05-29 22:33:25 -07:00
llc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-05-09 15:59:24 -04:00
mac80211 Some more work for 4.7, notably: 2016-05-12 11:46:58 -04:00
mac802154
mpls skbuff: introduce skb_gso_validate_mtu 2016-06-03 19:37:21 -04:00
netfilter net: sched: do not acquire qdisc spinlock in qdisc/class stats dump 2016-06-07 16:37:14 -07:00
netlabel
netlink net/netlink/af_netlink.h: Remove unused structure. 2016-06-09 22:26:24 -07:00
netrom
nfc nfc: nci: Add nci_nfcc_loopback to the nci core 2016-05-04 01:48:16 +02:00
openvswitch ovs: set name assign type of internal port 2016-06-02 18:05:47 -04:00
packet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-04-23 18:51:33 -04:00
phonet
qrtr Merge tag 'qcom-soc-for-4.7-2' into net-next 2016-05-17 14:11:19 -04:00
rds Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-05-20 20:01:26 -07:00
rfkill
rose
rxrpc rxrpc: Simplify connect() implementation and simplify sendmsg() op 2016-06-09 23:30:12 -07:00
sched net: sched: fix qdisc->running lockdep annotations 2016-06-09 13:28:37 -07:00
sctp sctp: Fix warning in sctp_packet_transmit_chunk() 2016-06-03 22:53:26 -07:00
sunrpc NFS client updates for Linux 4.7 2016-05-26 10:33:33 -07:00
switchdev switchdev: pass pointer to fib_info instead of copy 2016-05-17 13:58:49 -04:00
tipc tipc: change node timer unit from jiffies to ms 2016-06-08 11:27:02 -07:00
unix
vmw_vsock Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-05-09 15:59:24 -04:00
wimax
wireless mm/page_ref: use page_ref helper instead of direct modification of _count 2016-05-19 19:12:14 -07:00
x25 net: fix a kernel infoleak in x25 module 2016-05-09 22:45:33 -04:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-05-09 15:59:24 -04:00
compat.c
Kconfig bpf: add generic constant blinding for use in jits 2016-05-16 13:49:32 -04:00
Makefile net: Add Qualcomm IPC router 2016-05-08 23:46:14 -04:00
socket.c fs: poll/select/recvmmsg: use timespec64 for timeout events 2016-05-19 19:12:14 -07:00
sysctl_net.c