syzbot

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WARNING: CPU: 0 PID: 2621 at net/ipv4/tcp.c:2131 tcp_close+0xc30/0xfa0 net/ipv4/tcp.c:2131()
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 2621 Comm: syz-executor.0 Not tainted 4.4.174+ #4
 0000000000000000 a2ca428fb2c80fe7 ffff8801d0d7fbb0 ffffffff81aad1a1
 0000000000000000 ffffffff82835ee0 ffffffff82a85940 0000000000000853
 ffffffff823fe910 ffff8801d0d7fc90 ffffffff813a48c2 0000000041b58ab3
Call Trace:
 [<ffffffff81aad1a1>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81aad1a1>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff813a48c2>] panic+0x1b9/0x37b kernel/panic.c:112
 [<ffffffff813a4ab9>] warn_slowpath_common kernel/panic.c:455 [inline]
 [<ffffffff813a4ab9>] warn_slowpath_common.cold+0x20/0x20 kernel/panic.c:435
 [<ffffffff810d3aaa>] warn_slowpath_null+0x2a/0x30 kernel/panic.c:492
 [<ffffffff823fe910>] tcp_close+0xc30/0xfa0 net/ipv4/tcp.c:2131
 [<ffffffff824a6a3f>] inet_release+0xff/0x1d0 net/ipv4/af_inet.c:435
 [<ffffffff82599893>] inet6_release+0x53/0x80 net/ipv6/af_inet6.c:439
 [<ffffffff821d36a5>] __sock_release+0xd5/0x260 net/socket.c:592
 [<ffffffff821d384b>] sock_close+0x1b/0x30 net/socket.c:1050
 [<ffffffff8149c8c6>] __fput+0x246/0x710 fs/file_table.c:208
 [<ffffffff8149ce16>] ____fput+0x16/0x20 fs/file_table.c:244
 [<ffffffff8112f352>] task_work_run+0x202/0x2b0 kernel/task_work.c:115
 [<ffffffff81003dca>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff81003dca>] exit_to_usermode_loop+0x14a/0x170 arch/x86/entry/common.c:188
 [<ffffffff8100569b>] prepare_exit_to_usermode arch/x86/entry/common.c:221 [inline]
 [<ffffffff8100569b>] syscall_return_slowpath+0x25b/0x2e0 arch/x86/entry/common.c:286
 [<ffffffff82718ce1>] int_ret_from_sys_call+0x25/0xa3
Kernel Offset: disabled
Rebooting in 86400 seconds..