syzbot

------------[ cut here ]------------
WARNING: CPU: 0 PID: 9519 at ./arch/x86/include/asm/fpu/internal.h:530 __fpregs_activate arch/x86/include/asm/fpu/internal.h:530 [inline]()
WARNING: CPU: 0 PID: 9519 at ./arch/x86/include/asm/fpu/internal.h:530 fpregs_activate arch/x86/include/asm/fpu/internal.h:561 [inline]()
WARNING: CPU: 0 PID: 9519 at ./arch/x86/include/asm/fpu/internal.h:530 fpu__restore+0x206/0x270 arch/x86/kernel/fpu/core.c:382()
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 9519 Comm: syz-executor7 Not tainted 4.4.141-g1b37d68 #7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 75687611d8b725be ffff8800a4877a98 ffffffff81e0e18d
 ffffffff83a44200[  174.336635] TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
 ffff8801bb3c4800 ffffffff83a0ee40 0000000000000009
 0000000000000212 ffff8800a4877b58 ffffffff8140a1f4 0000000041b58ab3
Call Trace:
 [<ffffffff81e0e18d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81e0e18d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff8140a1f4>] panic+0x19e/0x38d kernel/panic.c:112
 [<ffffffff8140a418>] warn_slowpath_common.cold.6+0x20/0x20 kernel/panic.c:455
 [<ffffffff811301a9>] warn_slowpath_null+0x29/0x30 kernel/panic.c:492
 [<ffffffff81028196>] __fpregs_activate arch/x86/include/asm/fpu/internal.h:530 [inline]
 [<ffffffff81028196>] fpregs_activate arch/x86/include/asm/fpu/internal.h:561 [inline]
 [<ffffffff81028196>] fpu__restore+0x206/0x270 arch/x86/kernel/fpu/core.c:382
 [<ffffffff8102b554>] __fpu__restore_sig+0x3a4/0xa00 arch/x86/kernel/fpu/signal.c:324
 [<ffffffff8102bff7>] fpu__restore_sig+0x87/0xe0 arch/x86/kernel/fpu/signal.c:362
 [<ffffffff81115f3d>] ia32_restore_sigcontext+0x43d/0x500 arch/x86/ia32/ia32_signal.c:108
 [<ffffffff811168e7>] sys32_rt_sigreturn+0x1b7/0x270 arch/x86/ia32/ia32_signal.c:156
 [<ffffffff81006d96>] do_syscall_32_irqs_on arch/x86/entry/common.c:393 [inline]
 [<ffffffff81006d96>] do_fast_syscall_32+0x326/0x8b0 arch/x86/entry/common.c:460
 [<ffffffff838c456a>] sysenter_flags_fixed+0xd/0x17
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..