==================================================================
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: 0 PID: 20818 Comm: syz-executor7 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
 garp_join_timer_arm net/802/garp.c:401 [inline]
 garp_join_timer+0x375/0x390 net/802/garp.c:414
 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:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:66
RSP: 0018:ffff8801ab69ef98 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: ffff8801a5edf1ff RBX: ffff8801ab69f130 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 00000000ffffffff RDI: ffff8801a5edf131
RBP: ffff8801ab69f038 R08: 0000000001080020 R09: ffff8801a5edf130
R10: 0000000000000000 R11: ffffffff881c6d90 R12: 0000000000000001
R13: ffffffff8acc6390 R14: 0000000000000001 R15: ffff88009b4f1d40
 kfree+0x7f/0x29e0 mm/slub.c:3959
 __vunmap+0x281/0x3e0 mm/vmalloc.c:1545
 vfree+0x79/0x170 mm/vmalloc.c:1606
 netlink_skb_destructor+0x1dd/0x2e0 net/netlink/af_netlink.c:374
 skb_release_head_state+0x2f1/0x520 net/core/skbuff.c:613
 skb_release_all net/core/skbuff.c:626 [inline]
 __kfree_skb+0x57/0x280 net/core/skbuff.c:642
 consume_skb+0x35d/0x3b0 net/core/skbuff.c:702
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0x1692/0x1750 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x104f/0x1350 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 kernel_sendmsg+0x22a/0x2d0 net/socket.c:647
 sock_no_sendpage+0x1c8/0x250 net/core/sock.c:2642
 kernel_sendpage net/socket.c:3323 [inline]
 sock_sendpage+0x1ef/0x2e0 net/socket.c:854
 pipe_to_sendpage+0x321/0x440 fs/splice.c:451
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x4a5/0xf50 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 generic_splice_sendpage+0x1c6/0x2a0 fs/splice.c:832
 do_splice_from fs/splice.c:851 [inline]
 direct_splice_actor+0x19e/0x200 fs/splice.c:1018
 splice_direct_to_actor+0x767/0x1040 fs/splice.c:973
 do_splice_direct+0x335/0x540 fs/splice.c:1061
 do_sendfile+0x107b/0x1e40 fs/read_write.c:1440
 __do_sys_sendfile64 fs/read_write.c:1495 [inline]
 __se_sys_sendfile64 fs/read_write.c:1487 [inline]
 __x64_sys_sendfile64+0x218/0x390 fs/read_write.c:1487
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455a99
RSP: 002b:00007fa79996dc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fa79996e6d4 RCX: 0000000000455a99
RDX: 00000000200000c0 RSI: 0000000000000016 RDI: 0000000000000015
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000080000002 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c0b12 R14: 00000000004d0920 R15: 0000000000000000

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
 garp_join_timer_arm net/802/garp.c:401 [inline]
 garp_join_timer+0x375/0x390 net/802/garp.c:414
 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: ----__wait111@rcu_gp_kthread
Variable was created at:
 rcu_gp_kthread+0x9c/0x38d0 kernel/rcu/tree.c:2181
 kthread+0x4db/0x6c0 kernel/kthread.c:241
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