------------[ cut here ]------------
WARNING: CPU: 1 PID: 3320 at kernel/signal.c:334 task_participate_group_stop+0x1de/0x220 kernel/signal.c:334
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 3320 Comm: syz-executor0 Not tainted 4.9.40-g682c1e3 #12
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d9497a20 ffffffff81d8de49 ffffffff83a46b40 ffff8801d9497af8
 ffffffff83a4d600 ffffffff8115d19e 0000000000000009 ffff8801d9497ae8
 ffffffff81429c91 0000000041b58ab3 ffffffff841835f0 ffffffff81429ad5
Call Trace:
 [<ffffffff81d8de49>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d8de49>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81429c91>] panic+0x1bc/0x3a8 kernel/panic.c:179
 [<ffffffff81131e54>] __warn+0x1c4/0x1e0 kernel/panic.c:542
sock: sock_set_timeout: `syz-executor2' (pid 12404) tries to set negative timeout
 [<ffffffff811320bc>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
 [<ffffffff8115d19e>] task_participate_group_stop+0x1de/0x220 kernel/signal.c:334
 [<ffffffff811616ab>] do_signal_stop+0x19b/0x7b0 kernel/signal.c:2022
 [<ffffffff811661ec>] get_signal+0x4bc/0x1600 kernel/signal.c:2278
 [<ffffffff81052b97>] do_signal+0x87/0x1960 arch/x86/kernel/signal.c:807
 [<ffffffff81003a35>] exit_to_usermode_loop+0xe5/0x130 arch/x86/entry/common.c:156
 [<ffffffff81006350>] prepare_exit_to_usermode arch/x86/entry/common.c:190 [inline]
 [<ffffffff81006350>] syscall_return_slowpath+0x1a0/0x1e0 arch/x86/entry/common.c:259
 [<ffffffff838a1766>] entry_SYSCALL_64_fastpath+0xc4/0xc6
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..