------------[ cut here ]------------ 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: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [] panic+0x1b9/0x37b kernel/panic.c:112 [] warn_slowpath_common kernel/panic.c:455 [inline] [] warn_slowpath_common.cold+0x20/0x20 kernel/panic.c:435 [] warn_slowpath_null+0x2a/0x30 kernel/panic.c:492 [] tcp_close+0xc30/0xfa0 net/ipv4/tcp.c:2131 [] inet_release+0xff/0x1d0 net/ipv4/af_inet.c:435 [] inet6_release+0x53/0x80 net/ipv6/af_inet6.c:439 [] __sock_release+0xd5/0x260 net/socket.c:592 [] sock_close+0x1b/0x30 net/socket.c:1050 [] __fput+0x246/0x710 fs/file_table.c:208 [] ____fput+0x16/0x20 fs/file_table.c:244 [] task_work_run+0x202/0x2b0 kernel/task_work.c:115 [] tracehook_notify_resume include/linux/tracehook.h:191 [inline] [] exit_to_usermode_loop+0x14a/0x170 arch/x86/entry/common.c:188 [] prepare_exit_to_usermode arch/x86/entry/common.c:221 [inline] [] syscall_return_slowpath+0x25b/0x2e0 arch/x86/entry/common.c:286 [] int_ret_from_sys_call+0x25/0xa3 Kernel Offset: disabled Rebooting in 86400 seconds..