NFS: bad mount option value specified: v;
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BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:673 [inline]
BUG: KASAN: use-after-free in enqueue_timer kernel/time/timer.c:520 [inline]
BUG: KASAN: use-after-free in __mod_timer kernel/time/timer.c:1021 [inline]
BUG: KASAN: use-after-free in mod_timer+0x11d3/0x15b0 kernel/time/timer.c:1071
Write of size 8 at addr ffff8801c1b43540 by task syz-executor2/8883

CPU: 1 PID: 8883 Comm: syz-executor2 Not tainted 4.14.0-rc4+ #132
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report.c:435
 hlist_add_head include/linux/list.h:673 [inline]
 enqueue_timer kernel/time/timer.c:520 [inline]
 __mod_timer kernel/time/timer.c:1021 [inline]
 mod_timer+0x11d3/0x15b0 kernel/time/timer.c:1071
 sk_reset_timer+0x22/0x50 net/core/sock.c:2669
 inet_csk_reset_xmit_timer include/net/inet_connection_sock.h:243 [inline]
 dccp_send_close+0x2ea/0x380 net/dccp/output.c:700
 dccp_terminate_connection net/dccp/proto.c:974 [inline]
 dccp_close+0x8b6/0xc10 net/dccp/proto.c:1037
 inet_release+0xed/0x1c0 net/ipv4/af_inet.c:425
 sock_release+0x8d/0x1e0 net/socket.c:597
 sock_close+0x16/0x20 net/socket.c:1126
 __fput+0x327/0x7e0 fs/file_table.c:210
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x199/0x270 kernel/task_work.c:112
 exit_task_work include/linux/task_work.h:21 [inline]
 do_exit+0x9b5/0x1ad0 kernel/exit.c:865
 do_group_exit+0x149/0x400 kernel/exit.c:968
 get_signal+0x73f/0x16d0 kernel/signal.c:2334
 do_signal+0x94/0x1ee0 arch/x86/kernel/signal.c:808
 exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath+0x42f/0x510 arch/x86/entry/common.c:266
 entry_SYSCALL_64_fastpath+0xbc/0xbe
RIP: 0033:0x4520a9
RSP: 002b:00007f7f0ca33cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 0000000000718188 RCX: 00000000004520a9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718188
RBP: 0000000000718160 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000a6f7ef R14: 00007f7f0ca349c0 R15: 0000000000000004

Allocated by task 8881:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 __do_kmalloc_node mm/slab.c:3689 [inline]
 __kmalloc_node+0x47/0x70 mm/slab.c:3696
 kmalloc_node include/linux/slab.h:535 [inline]
 kvmalloc_node+0x64/0xd0 mm/util.c:397
 kvmalloc include/linux/mm.h:529 [inline]
 kvzalloc include/linux/mm.h:537 [inline]
 alloc_netdev_mqs+0x16e/0xed0 net/core/dev.c:8023
 tun_set_iff drivers/net/tun.c:2024 [inline]
 __tun_chr_ioctl+0x12b2/0x3d20 drivers/net/tun.c:2278
 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2523
 vfs_ioctl fs/ioctl.c:45 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685
 SYSC_ioctl fs/ioctl.c:700 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Freed by task 8881:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xca/0x250 mm/slab.c:3820
 kvfree+0x36/0x60 mm/util.c:416
 netdev_freemem net/core/dev.c:7975 [inline]
 free_netdev+0x2cf/0x360 net/core/dev.c:8137
 tun_set_iff drivers/net/tun.c:2107 [inline]
 __tun_chr_ioctl+0x2cea/0x3d20 drivers/net/tun.c:2278
 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2523
 vfs_ioctl fs/ioctl.c:45 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685
 SYSC_ioctl fs/ioctl.c:700 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691
 entry_SYSCALL_64_fastpath+0x1f/0xbe

The buggy address belongs to the object at ffff8801c1b40200
 which belongs to the cache kmalloc-16384 of size 16384
The buggy address is located 13120 bytes inside of
 16384-byte region [ffff8801c1b40200, ffff8801c1b44200)
The buggy address belongs to the page:
page:ffffea000706d000 count:1 mapcount:0 mapping:ffff8801c1b40200 index:0x0 compound_mapcount: 0
flags: 0x200000000008100(slab|head)
raw: 0200000000008100 ffff8801c1b40200 0000000000000000 0000000100000001
raw: ffffea000750ac20 ffffea0007664c20 ffff8801dac02200 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c1b43400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801c1b43480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801c1b43500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff8801c1b43580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801c1b43600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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