cd1aa9c2c6
After set fb_tunnels_only_for_init_net to 1, the itn->fb_tunnel_dev will
be NULL and will cause following crash:
[ 2742.849298] BUG: unable to handle kernel NULL pointer dereference at 0000000000000941
[ 2742.851380] PGD 800000042c21a067 P4D 800000042c21a067 PUD 42aaed067 PMD 0
[ 2742.852818] Oops: 0002 [#1] SMP PTI
[ 2742.853570] CPU: 7 PID: 2484 Comm: unshare Kdump: loaded Not tainted 4.18.0-rc8+ #2
[ 2742.855163] Hardware name: Fedora Project OpenStack Nova, BIOS seabios-1.7.5-11.el7 04/01/2014
[ 2742.856970] RIP: 0010:vti_init_net+0x3a/0x50 [ip_vti]
[ 2742.858034] Code: 90 83 c0 48 c7 c2 20 a1 83 c0 48 89 fb e8 6e 3b f6 ff 85 c0 75 22 8b 0d f4 19 00 00 48 8b 93 00 14 00 00 48 8b 14 ca 48 8b 12 <c6> 82 41 09 00 00 04 c6 82 38 09 00 00 45 5b c3 66 0f 1f 44 00 00
[ 2742.861940] RSP: 0018:ffff9be28207fde0 EFLAGS: 00010246
[ 2742.863044] RAX: 0000000000000000 RBX: ffff8a71ebed4980 RCX: 0000000000000013
[ 2742.864540] RDX: 0000000000000000 RSI: 0000000000000013 RDI: ffff8a71ebed4980
[ 2742.866020] RBP: ffff8a71ea717000 R08: ffffffffc083903c R09: ffff8a71ea717000
[ 2742.867505] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a71ebed4980
[ 2742.868987] R13: 0000000000000013 R14: ffff8a71ea5b49c0 R15: 0000000000000000
[ 2742.870473] FS: 00007f02266c9740(0000) GS:ffff8a71ffdc0000(0000) knlGS:0000000000000000
[ 2742.872143] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2742.873340] CR2: 0000000000000941 CR3: 000000042bc20006 CR4: 00000000001606e0
[ 2742.874821] Call Trace:
[ 2742.875358] ops_init+0x38/0xf0
[ 2742.876078] setup_net+0xd9/0x1f0
[ 2742.876789] copy_net_ns+0xb7/0x130
[ 2742.877538] create_new_namespaces+0x11a/0x1d0
[ 2742.878525] unshare_nsproxy_namespaces+0x55/0xa0
[ 2742.879526] ksys_unshare+0x1a7/0x330
[ 2742.880313] __x64_sys_unshare+0xe/0x20
[ 2742.881131] do_syscall_64+0x5b/0x180
[ 2742.881933] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reproduce:
echo 1 > /proc/sys/net/core/fb_tunnels_only_for_init_net
modprobe ip_vti
unshare -n
Fixes:
|
||
---|---|---|
.. | ||
bpfilter | ||
netfilter | ||
af_inet.c | ||
ah4.c | ||
arp.c | ||
cipso_ipv4.c | ||
datagram.c | ||
devinet.c | ||
esp4_offload.c | ||
esp4.c | ||
fib_frontend.c | ||
fib_lookup.h | ||
fib_notifier.c | ||
fib_rules.c | ||
fib_semantics.c | ||
fib_trie.c | ||
fou.c | ||
gre_demux.c | ||
gre_offload.c | ||
icmp.c | ||
igmp.c | ||
inet_connection_sock.c | ||
inet_diag.c | ||
inet_fragment.c | ||
inet_hashtables.c | ||
inet_timewait_sock.c | ||
inetpeer.c | ||
ip_forward.c | ||
ip_fragment.c | ||
ip_gre.c | ||
ip_input.c | ||
ip_options.c | ||
ip_output.c | ||
ip_sockglue.c | ||
ip_tunnel_core.c | ||
ip_tunnel.c | ||
ip_vti.c | ||
ipcomp.c | ||
ipconfig.c | ||
ipip.c | ||
ipmr_base.c | ||
ipmr.c | ||
Kconfig | ||
Makefile | ||
metrics.c | ||
netfilter.c | ||
netlink.c | ||
ping.c | ||
proc.c | ||
protocol.c | ||
raw_diag.c | ||
raw.c | ||
route.c | ||
syncookies.c | ||
sysctl_net_ipv4.c | ||
tcp_bbr.c | ||
tcp_bic.c | ||
tcp_cdg.c | ||
tcp_cong.c | ||
tcp_cubic.c | ||
tcp_dctcp.c | ||
tcp_diag.c | ||
tcp_fastopen.c | ||
tcp_highspeed.c | ||
tcp_htcp.c | ||
tcp_hybla.c | ||
tcp_illinois.c | ||
tcp_input.c | ||
tcp_ipv4.c | ||
tcp_lp.c | ||
tcp_metrics.c | ||
tcp_minisocks.c | ||
tcp_nv.c | ||
tcp_offload.c | ||
tcp_output.c | ||
tcp_rate.c | ||
tcp_recovery.c | ||
tcp_scalable.c | ||
tcp_timer.c | ||
tcp_ulp.c | ||
tcp_vegas.c | ||
tcp_vegas.h | ||
tcp_veno.c | ||
tcp_westwood.c | ||
tcp_yeah.c | ||
tcp.c | ||
tunnel4.c | ||
udp_diag.c | ||
udp_impl.h | ||
udp_offload.c | ||
udp_tunnel.c | ||
udp.c | ||
udplite.c | ||
xfrm4_input.c | ||
xfrm4_mode_beet.c | ||
xfrm4_mode_transport.c | ||
xfrm4_mode_tunnel.c | ||
xfrm4_output.c | ||
xfrm4_policy.c | ||
xfrm4_protocol.c | ||
xfrm4_state.c | ||
xfrm4_tunnel.c |