syzbot

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WARNING: CPU: 0 PID: 3816 at net/ipv4/tcp_input.c:1992 tcp_enter_loss+0xe92/0x1180 net/ipv4/tcp_input.c:1992
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 3816 Comm: syz-executor428 Not tainted 4.9.96-g8c01d00 #11
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801c7527968 ffffffff81eb0b69 ffffffff83a484a0 00000000ffffffff
 0000000000000000 0000000000000000 00000000000007c8 ffff8801c7527a28
 ffffffff8141f975 0000000041b58ab3 ffffffff841b8030 ffffffff8141f7b6
Call Trace:
 [<ffffffff81eb0b69>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb0b69>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8141f975>] panic+0x1bf/0x3bc kernel/panic.c:179
 [<ffffffff8141fc61>] __warn.cold.9+0xc1/0x17f kernel/panic.c:542
 [<ffffffff8113461c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
 [<ffffffff83388d22>] tcp_enter_loss+0xe92/0x1180 net/ipv4/tcp_input.c:1992
 [<ffffffff833b25a2>] tcp_retransmit_timer+0x8e2/0x2290 net/ipv4/tcp_timer.c:505
 [<ffffffff833b4141>] tcp_write_timer_handler+0x1f1/0x7a0 net/ipv4/tcp_timer.c:591
 [<ffffffff833ad156>] tcp_release_cb+0x1b6/0x230 net/ipv4/tcp_output.c:826
 [<ffffffff8302000e>] release_sock+0xbe/0x1c0 net/core/sock.c:2526
 [<ffffffff83361c61>] do_tcp_setsockopt.isra.40+0x261/0x1d30 net/ipv4/tcp.c:2745
 [<ffffffff833637e6>] tcp_setsockopt+0xb6/0xe0 net/ipv4/tcp.c:2757
 [<ffffffff8301875a>] sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706
 [<ffffffff83015516>] SYSC_setsockopt net/socket.c:1772 [inline]
 [<ffffffff83015516>] SyS_setsockopt+0x166/0x260 net/socket.c:1751
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f3313>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..