Dead loop on virtual device ip6tnl0, fix it urgently!
==================================================================
Dead loop on virtual device ip6tnl0, fix it urgently!
BUG: KASAN: slab-out-of-bounds in ip6_tnl_xmit2+0x2043/0x20d0 net/ipv6/ip6_tunnel.c:987
Read of size 16 at addr ffff8800b5c3d930 by task syz-executor3/4469

CPU: 1 PID: 4469 Comm: syz-executor3 Not tainted 4.4.128-ged3b23f #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 72f1aff974fb2356 ffff8801c6d26b20 ffffffff81e0daad
 ffffea0002d70f00 ffff8800b5c3d930 0000000000000000 ffff8800b5c3d938
 ffff8800b9980000 ffff8801c6d26b58 ffffffff815150ac ffff8800b5c3d930
Call Trace:
 [<ffffffff81e0daad>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81e0daad>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff815150ac>] print_address_description+0x6c/0x216 mm/kasan/report.c:252
 [<ffffffff815153cb>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff815153cb>] kasan_report.cold.7+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff814f8f9f>] __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:439
 [<ffffffff83543633>] ip6_tnl_xmit2+0x2043/0x20d0 net/ipv6/ip6_tunnel.c:987
 [<ffffffff83543fd0>] ip4ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1129 [inline]
 [<ffffffff83543fd0>] ip6_tnl_xmit+0x910/0xc60 net/ipv6/ip6_tunnel.c:1203
 [<ffffffff82f86eb1>] __netdev_start_xmit include/linux/netdevice.h:3743 [inline]
 [<ffffffff82f86eb1>] netdev_start_xmit include/linux/netdevice.h:3752 [inline]
 [<ffffffff82f86eb1>] xmit_one net/core/dev.c:2759 [inline]
 [<ffffffff82f86eb1>] dev_hard_start_xmit+0x7b1/0x11c0 net/core/dev.c:2775
 [<ffffffff82f89240>] __dev_queue_xmit+0x16c0/0x1c80 net/core/dev.c:3207
 [<ffffffff82f89817>] dev_queue_xmit+0x17/0x20 net/core/dev.c:3241
 [<ffffffff82f9b015>] neigh_direct_output+0x15/0x20 net/core/neighbour.c:1358
 [<ffffffff832131db>] dst_neigh_output include/net/dst.h:461 [inline]
 [<ffffffff832131db>] ip_finish_output2+0x6ab/0x1110 net/ipv4/ip_output.c:213
 [<ffffffff832155cb>] ip_do_fragment+0x198b/0x2150 net/ipv4/ip_output.c:633
 [<ffffffff83215ed3>] ip_fragment.constprop.50+0x143/0x200 net/ipv4/ip_output.c:503
 [<ffffffff83216654>] ip_finish_output+0x6c4/0xbc0 net/ipv4/ip_output.c:286
 [<ffffffff8321a0e9>] NF_HOOK_COND include/linux/netfilter.h:240 [inline]
 [<ffffffff8321a0e9>] ip_output+0x219/0x4c0 net/ipv4/ip_output.c:362
 [<ffffffff8321702b>] dst_output include/net/dst.h:498 [inline]
 [<ffffffff8321702b>] ip_local_out+0x9b/0x180 net/ipv4/ip_output.c:119
 [<ffffffff8321cccc>] ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1450
 [<ffffffff832c5093>] udp_send_skb+0x5c3/0xc60 net/ipv4/udp.c:842
 [<ffffffff832cdc4e>] udp_sendmsg+0x16ce/0x1bb0 net/ipv4/udp.c:1070
 [<ffffffff83492c0d>] udpv6_sendmsg+0x12cd/0x24c0 net/ipv6/udp.c:1173
 [<ffffffff832fd7a3>] inet_sendmsg+0x203/0x4d0 net/ipv4/af_inet.c:755
 [<ffffffff82f1ba9c>] sock_sendmsg_nosec net/socket.c:625 [inline]
 [<ffffffff82f1ba9c>] sock_sendmsg+0xcc/0x110 net/socket.c:635
 [<ffffffff82f1d261>] ___sys_sendmsg+0x441/0x880 net/socket.c:1962
 [<ffffffff82f1f83e>] __sys_sendmmsg+0x12e/0x2e0 net/socket.c:2047
 [<ffffffff82f1fa25>] SYSC_sendmmsg net/socket.c:2077 [inline]
 [<ffffffff82f1fa25>] SyS_sendmmsg+0x35/0x60 net/socket.c:2072
 [<ffffffff838be765>] entry_SYSCALL_64_fastpath+0x22/0x9e

Allocated by task 4469:
 [<ffffffff810341d6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814f7f73>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814f8257>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814f8257>] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:616
 [<ffffffff814f4974>] __kmalloc+0x124/0x310 mm/slub.c:3613
 [<ffffffff82fabd36>] kmalloc include/linux/slab.h:481 [inline]
 [<ffffffff82fabd36>] kzalloc include/linux/slab.h:620 [inline]
 [<ffffffff82fabd36>] neigh_alloc net/core/neighbour.c:285 [inline]
 [<ffffffff82fabd36>] __neigh_create+0x1d6/0x1b20 net/core/neighbour.c:457
 [<ffffffff831ec2bd>] neigh_create include/net/neighbour.h:313 [inline]
 [<ffffffff831ec2bd>] ipv4_neigh_lookup+0x4dd/0x700 net/ipv4/route.c:464
 [<ffffffff83541c03>] dst_neigh_lookup include/net/dst.h:466 [inline]
 [<ffffffff83541c03>] ip6_tnl_xmit2+0x613/0x20d0 net/ipv6/ip6_tunnel.c:982
 [<ffffffff83543fd0>] ip4ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1129 [inline]
 [<ffffffff83543fd0>] ip6_tnl_xmit+0x910/0xc60 net/ipv6/ip6_tunnel.c:1203
 [<ffffffff82f86eb1>] __netdev_start_xmit include/linux/netdevice.h:3743 [inline]
 [<ffffffff82f86eb1>] netdev_start_xmit include/linux/netdevice.h:3752 [inline]
 [<ffffffff82f86eb1>] xmit_one net/core/dev.c:2759 [inline]
 [<ffffffff82f86eb1>] dev_hard_start_xmit+0x7b1/0x11c0 net/core/dev.c:2775
 [<ffffffff82f89240>] __dev_queue_xmit+0x16c0/0x1c80 net/core/dev.c:3207
 [<ffffffff82f89817>] dev_queue_xmit+0x17/0x20 net/core/dev.c:3241
 [<ffffffff82f9b015>] neigh_direct_output+0x15/0x20 net/core/neighbour.c:1358
 [<ffffffff832131db>] dst_neigh_output include/net/dst.h:461 [inline]
 [<ffffffff832131db>] ip_finish_output2+0x6ab/0x1110 net/ipv4/ip_output.c:213
 [<ffffffff832155cb>] ip_do_fragment+0x198b/0x2150 net/ipv4/ip_output.c:633
 [<ffffffff83215ed3>] ip_fragment.constprop.50+0x143/0x200 net/ipv4/ip_output.c:503
 [<ffffffff83216654>] ip_finish_output+0x6c4/0xbc0 net/ipv4/ip_output.c:286
 [<ffffffff8321a0e9>] NF_HOOK_COND include/linux/netfilter.h:240 [inline]
 [<ffffffff8321a0e9>] ip_output+0x219/0x4c0 net/ipv4/ip_output.c:362
 [<ffffffff8321702b>] dst_output include/net/dst.h:498 [inline]
 [<ffffffff8321702b>] ip_local_out+0x9b/0x180 net/ipv4/ip_output.c:119
 [<ffffffff8321cccc>] ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1450
 [<ffffffff832c5093>] udp_send_skb+0x5c3/0xc60 net/ipv4/udp.c:842
 [<ffffffff832cdc4e>] udp_sendmsg+0x16ce/0x1bb0 net/ipv4/udp.c:1070
 [<ffffffff83492c0d>] udpv6_sendmsg+0x12cd/0x24c0 net/ipv6/udp.c:1173
 [<ffffffff832fd7a3>] inet_sendmsg+0x203/0x4d0 net/ipv4/af_inet.c:755
 [<ffffffff82f1ba9c>] sock_sendmsg_nosec net/socket.c:625 [inline]
 [<ffffffff82f1ba9c>] sock_sendmsg+0xcc/0x110 net/socket.c:635
 [<ffffffff82f1d261>] ___sys_sendmsg+0x441/0x880 net/socket.c:1962
 [<ffffffff82f1f83e>] __sys_sendmmsg+0x12e/0x2e0 net/socket.c:2047
 [<ffffffff82f1fa25>] SYSC_sendmmsg net/socket.c:2077 [inline]
 [<ffffffff82f1fa25>] SyS_sendmmsg+0x35/0x60 net/socket.c:2072
 [<ffffffff838be765>] entry_SYSCALL_64_fastpath+0x22/0x9e

Freed by task 3932:
 [<ffffffff810341d6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814f7f73>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814f88a2>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814f88a2>] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:589
 [<ffffffff814f5da4>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff814f5da4>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff814f5da4>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff814f5da4>] kfree+0xf4/0x310 mm/slub.c:3749
 [<ffffffff8146c53b>] kvfree+0x4b/0x60 mm/util.c:323
 [<ffffffff8315c3ef>] xt_free_table_info+0x14f/0x1b0 net/netfilter/x_tables.c:1019
 [<ffffffff83517260>] __do_replace+0x400/0x620 net/ipv6/netfilter/ip6_tables.c:1259
 [<ffffffff8351f411>] do_replace net/ipv6/netfilter/ip6_tables.c:1315 [inline]
 [<ffffffff8351f411>] do_ip6t_set_ctl+0x2e1/0x450 net/ipv6/netfilter/ip6_tables.c:1862
 [<ffffffff830c413d>] nf_sockopt net/netfilter/nf_sockopt.c:105 [inline]
 [<ffffffff830c413d>] nf_setsockopt+0x6d/0xc0 net/netfilter/nf_sockopt.c:114
 [<ffffffff834800b8>] ipv6_setsockopt+0xc8/0x130 net/ipv6/ipv6_sockglue.c:909
 [<ffffffff83241378>] tcp_setsockopt+0x88/0xe0 net/ipv4/tcp.c:2641
 [<ffffffff82f2212a>] sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2659
 [<ffffffff82f1f046>] SYSC_setsockopt net/socket.c:1767 [inline]
 [<ffffffff82f1f046>] SyS_setsockopt+0x166/0x260 net/socket.c:1746
 [<ffffffff838be8cb>] tracesys_phase2+0x94/0x99

The buggy address belongs to the object at ffff8800b5c3d680
 which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 688 bytes inside of
 1024-byte region [ffff8800b5c3d680, ffff8800b5c3da80)
The buggy address belongs to the page:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 3936 Comm: syz-executor3 Not tainted 4.4.128-ged3b23f #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8800a3689800 task.stack: ffff8800ba9d0000
RIP: 0010:[<ffffffff81e6f5c1>]  [<ffffffff81e6f5c1>] lookup_object lib/debugobjects.c:120 [inline]
RIP: 0010:[<ffffffff81e6f5c1>]  [<ffffffff81e6f5c1>] debug_object_deactivate+0x191/0x340 lib/debugobjects.c:465
RSP: 0018:ffff8801db207cf0  EFLAGS: 00010803
RAX: dffffc0000000000 RBX: c42fe8df89480b0f RCX: 1885fd1bf1290164
RDX: 1ffffffff0b43f3f RSI: ffffffff844c64e0 RDI: c42fe8df89480b27
RBP: ffff8801db207da8 R08: ffffffff85363dd0 R09: 0000000000000001
R10: 0000000000000001 R11: ffff8800a3689800 R12: 1ffff1003b640fa0
R13: ffffffff85a1f9e8 R14: ffff8801c6dc7b10 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff8148ca77 CR3: 00000000ab90a000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 0000000000000092 ffffffff844c64e0 0000000041b58ab3 ffffffff84208a1f
 ffffffff81e6f430 ffff8800a3689800 ffffed00146d141b ffff8800a368a0e0
 ffff8801db219658 0000000000000001 ffff8801db207d80 ffffffff81229442
Call Trace:
 <IRQ> 
 [<ffffffff8129d952>] debug_hrtimer_deactivate kernel/time/hrtimer.c:415 [inline]
 [<ffffffff8129d952>] debug_deactivate kernel/time/hrtimer.c:461 [inline]
 [<ffffffff8129d952>] __run_hrtimer kernel/time/hrtimer.c:1229 [inline]
 [<ffffffff8129d952>] __hrtimer_run_queues+0x222/0x1000 kernel/time/hrtimer.c:1324
 [<ffffffff8129f271>] hrtimer_interrupt+0x1b1/0x430 kernel/time/hrtimer.c:1358
 [<ffffffff810ad514>] local_apic_timer_interrupt+0x74/0xa0 arch/x86/kernel/apic/apic.c:901
 [<ffffffff838c138c>] smp_apic_timer_interrupt+0x7c/0xa0 arch/x86/kernel/apic/apic.c:925
 [<ffffffff838c02d0>] apic_timer_interrupt+0xa0/0xb0 arch/x86/entry/entry_64.S:741
 <EOI> 
 [<ffffffff81015dba>] dump_trace+0x17a/0x360 arch/x86/kernel/dumpstack_64.c:243
 [<ffffffff810341d6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814f7f73>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814f88a2>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814f88a2>] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:589
 [<ffffffff814f5a2e>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff814f5a2e>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff814f5a2e>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff814f5a2e>] kmem_cache_free+0xbe/0x340 mm/slub.c:2881
 [<ffffffff814b97f3>] anon_vma_chain_free mm/rmap.c:129 [inline]
 [<ffffffff814b97f3>] unlink_anon_vmas+0xb3/0x640 mm/rmap.c:397
 [<ffffffff81493f16>] free_pgtables+0xe6/0x330 mm/memory.c:540
 [<ffffffff814afb08>] exit_mmap+0x1d8/0x3a0 mm/mmap.c:2928
 [<ffffffff811253f8>] __mmput kernel/fork.c:715 [inline]
 [<ffffffff811253f8>] mmput+0xf8/0x2d0 kernel/fork.c:735
 [<ffffffff81135068>] exit_mm kernel/exit.c:444 [inline]
 [<ffffffff81135068>] do_exit+0x8d8/0x26b0 kernel/exit.c:746
 [<ffffffff8113b0c1>] do_group_exit+0x111/0x330 kernel/exit.c:889
 [<ffffffff8113b2fd>] SYSC_exit_group kernel/exit.c:900 [inline]
 [<ffffffff8113b2fd>] SyS_exit_group+0x1d/0x20 kernel/exit.c:898
 [<ffffffff838be765>] entry_SYSCALL_64_fastpath+0x22/0x9e
Code: a9 01 00 00 48 8b 1b 41 bf 01 00 00 00 48 85 db 74 42 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 18 41 83 c7 01 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f 85 0c 01 00 00 4c 3b 73 18 74 7d 48 89 d9 48 c1 
RIP  [<ffffffff81e6f5c1>] lookup_object lib/debugobjects.c:120 [inline]
RIP  [<ffffffff81e6f5c1>] debug_object_deactivate+0x191/0x340 lib/debugobjects.c:465
 RSP <ffff8801db207cf0>
---[ end trace a3a897126342b1e6 ]---