==================================================================
BUG: KMSAN: uninit-value in lock_timer_base kernel/time/timer.c:939 [inline]
BUG: KMSAN: uninit-value in __mod_timer+0x42d/0x2bf0 kernel/time/timer.c:1010
CPU: 1 PID: 4501 Comm: syz-executor4 Not tainted 4.17.0+ #9
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:620
 lock_timer_base kernel/time/timer.c:939 [inline]
 __mod_timer+0x42d/0x2bf0 kernel/time/timer.c:1010
 mod_timer+0x70/0x80 kernel/time/timer.c:1102
 can_stat_update+0x15ec/0x1860 net/can/proc.c:179
 call_timer_fn+0x280/0x5d0 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0xd96/0x11b0 kernel/time/timer.c:1666
 run_timer_softirq+0x43/0x70 kernel/time/timer.c:1692
 __do_softirq+0x592/0x979 kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x202/0x240 kernel/softirq.c:405
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:525
 smp_apic_timer_interrupt+0x64/0x90 arch/x86/kernel/apic/apic.c:1055
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:866
 </IRQ>
RIP: 0010:cleanup_mnt+0x262/0x4d0 fs/namespace.c:1170
RSP: 0018:ffff8801268cfc70 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffff8801b5638728 RCX: ffff880000000000
RDX: ffff8801704f4728 RSI: aaaaaaaaaaaab000 RDI: ffffea0000000000
RBP: ffff8801268cfcd8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff81db3850 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1181
 task_work_run+0x22e/0x2b0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop arch/x86/entry/common.c:166 [inline]
 prepare_exit_to_usermode+0x33c/0x3a0 arch/x86/entry/common.c:196
 syscall_return_slowpath+0xe9/0x710 arch/x86/entry/common.c:265
 do_syscall_64+0x1ad/0x230 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x458537
RSP: 002b:0000000000a3d9e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 000000000000029d RCX: 0000000000458537
RDX: 000000000000000c RSI: 0000000000000002 RDI: 0000000000a3f790
RBP: 0000000000a3f790 R08: 0000000000000001 R09: 0000000000f50940
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000831 R15: 000000000007edf3

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:282 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:297 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:689
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:464
 timer_set_idx kernel/time/timer.c:480 [inline]
 enqueue_timer kernel/time/timer.c:539 [inline]
 __internal_add_timer kernel/time/timer.c:548 [inline]
 internal_add_timer kernel/time/timer.c:590 [inline]
 __mod_timer+0x22a1/0x2bf0 kernel/time/timer.c:1055
 mod_timer+0x70/0x80 kernel/time/timer.c:1102
 can_stat_update+0x15ec/0x1860 net/can/proc.c:179
 call_timer_fn+0x280/0x5d0 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0xd96/0x11b0 kernel/time/timer.c:1666
 run_timer_softirq+0x43/0x70 kernel/time/timer.c:1692
 __do_softirq+0x592/0x979 kernel/softirq.c:285

Local variable description: ----heads@__run_timers
Variable was created at:
 __run_timers+0x84/0x11b0 kernel/time/timer.c:1651
 run_timer_softirq+0x43/0x70 kernel/time/timer.c:1692
==================================================================