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BUG: KASAN: alloca-out-of-bounds in tick_sched_handle+0x16d/0x180 kernel/time/tick-sched.c:162
Read of size 8 at addr ffff8801add6f210 by task syz-executor3/11222

CPU: 0 PID: 11222 Comm: syz-executor3 Not tainted 4.16.0+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b9/0x29f lib/dump_stack.c:53
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0xac/0x2f5 mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 tick_sched_handle+0x16d/0x180 kernel/time/tick-sched.c:162
 tick_sched_timer+0x42/0x130 kernel/time/tick-sched.c:1170
 __run_hrtimer kernel/time/hrtimer.c:1349 [inline]
 __hrtimer_run_queues+0x3e3/0x10a0 kernel/time/hrtimer.c:1411
 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1469
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
 smp_apic_timer_interrupt+0x15d/0x710 arch/x86/kernel/apic/apic.c:1050
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:862
 </IRQ>
RIP: 0010:__asan_allocas_unpoison+0xa/0x20 mm/kasan/kasan.c:771
RSP: 0018:ffff8801add6f230 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff12
RAX: 0000000000040000 RBX: ffffffff85e658f0 RCX: ffffc900074e4000
RDX: 0000000000000248 RSI: ffff8801add6f238 RDI: ffff8801add6f1a0
RBP: ffff8801add6f3a8 R08: ffff880194c38700 R09: fffffbfff15cff5b
R10: fffffbfff15cff5b R11: ffffffff8ae7fadf R12: 0000000000000000
R13: 0000000000000002 R14: 0000000000000000 R15: ffff8801cae85d00
 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2446
 nfnetlink_rcv+0x1fe/0x1ba0 net/netfilter/nfnetlink.c:513
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x58b/0x740 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x9d8/0xf80 net/netlink/af_netlink.c:1899
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:639
 sock_write_iter+0x35a/0x5a0 net/socket.c:908
 call_write_iter include/linux/fs.h:1782 [inline]
 do_iter_readv_writev+0x6a0/0x970 fs/read_write.c:680
 do_iter_write+0x185/0x5f0 fs/read_write.c:959
 vfs_writev+0x1c7/0x330 fs/read_write.c:1004
 do_writev+0x112/0x2f0 fs/read_write.c:1039
 SYSC_writev fs/read_write.c:1112 [inline]
 SyS_writev+0x27/0x30 fs/read_write.c:1109
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x455259
RSP: 002b:00007ffb1f914c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007ffb1f9156d4 RCX: 0000000000455259
RDX: 0000000000000001 RSI: 0000000020fb5ff0 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000006cd R14: 00000000006fd3d8 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0006b75bc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea0006b70101 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801add6f100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801add6f180: 00 00 00 00 ca ca ca ca 00 00 00 00 00 00 cb cb
>ffff8801add6f200: cb cb cb cb 00 00 00 00 00 00 00 00 00 00 00 00
                         ^
 ffff8801add6f280: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
 ffff8801add6f300: f8 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 00 00 00 00
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