==================================================================
BUG: KASAN: slab-out-of-bounds in find_first_bit+0xf7/0x100 lib/find_bit.c:107
------------[ cut here ]------------
Read of size 8 at addr ffff8801d6917310 by task kswapd0/1530
kernel BUG at mm/vmscan.c:593!

invalid opcode: 0000 [#1] SMP KASAN
CPU: 1 PID: 1530 Comm: kswapd0 Not tainted 4.18.0-rc3-next-20180706+ #1
CPU: 0 PID: 31024 Comm: syz-executor0 Not tainted 4.18.0-rc3-next-20180706+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
RIP: 0010:shrink_slab_memcg mm/vmscan.c:593 [inline]
RIP: 0010:shrink_slab+0xb3e/0xdb0 mm/vmscan.c:672
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
Code: 
8d a8 
fd 
ff 
ff 
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
f0 
48 
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x30d mm/kasan/report.c:412
0f 
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
b3 
 find_first_bit+0xf7/0x100 lib/find_bit.c:107
08 
 shrink_slab_memcg mm/vmscan.c:580 [inline]
 shrink_slab+0x5d0/0xdb0 mm/vmscan.c:672
e8 
3d 
b8 
da 
ff 
48 
 shrink_node+0x429/0x16a0 mm/vmscan.c:2736
8b 85 
c0 
fd 
ff 
ff 
c7 
00 
f8 
f8 
 kswapd_shrink_node mm/vmscan.c:3458 [inline]
 balance_pgdat+0x7ca/0x1010 mm/vmscan.c:3568
f8 
f8 
c6 
40 
 kswapd+0x82e/0x12f0 mm/vmscan.c:3790
04 
f8 
e9 
5d 
fb 
ff 
ff 
e8 
22 
b8 
da 
 kthread+0x345/0x410 kernel/kthread.c:246
ff 
<0f> 
0b 
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415
e8 1b 

b8 
Allocated by task 6588:
da 
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
ff 
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
48 
 __do_kmalloc_node mm/slab.c:3682 [inline]
 __kmalloc_node+0x47/0x70 mm/slab.c:3689
8b 9d 
 kmalloc_node include/linux/slab.h:555 [inline]
 kvmalloc_node+0x65/0xf0 mm/util.c:423
d8 
 kvmalloc include/linux/mm.h:557 [inline]
 memcg_expand_one_shrinker_map mm/memcontrol.c:341 [inline]
 memcg_expand_shrinker_maps+0x1b1/0x3c0 mm/memcontrol.c:416
fd ff 
 prealloc_memcg_shrinker mm/vmscan.c:185 [inline]
 prealloc_shrinker+0x29e/0x450 mm/vmscan.c:366
ff 
 alloc_super+0x8dd/0xb10 fs/super.c:264
 sget_userns+0x276/0x860 fs/super.c:615
31 
 sget+0x10b/0x150 fs/super.c:667
ff 
 mount_nodev+0x38/0x120 fs/super.c:1393
48 
 bpf_mount+0x34/0x40 kernel/bpf/inode.c:658
 legacy_get_tree+0x118/0x440 fs/fs_context.c:659
89 
 vfs_get_tree+0x1cb/0x5c0 fs/super.c:1751
 do_new_mount fs/namespace.c:2567 [inline]
 do_mount+0x6c1/0x1fb0 fs/namespace.c:2889
de 
 ksys_mount+0x12d/0x140 fs/namespace.c:3105
e8 
 __do_sys_mount fs/namespace.c:3119 [inline]
 __se_sys_mount fs/namespace.c:3116 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3116
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
3a 
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
b9 

Freed by task 1:
RSP: 0018:ffff880191d0e508 EFLAGS: 00010246
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
RAX: 0000000000040000 RBX: ffff880191d0e758 RCX: ffffc90001b6a000
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
RDX: 0000000000040000 RSI: ffffffff81a1c23e RDI: 0000000000000007
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xd9/0x260 mm/slab.c:3813
 acpi_os_free include/acpi/platform/aclinuxex.h:62 [inline]
 acpi_ex_start_trace_method+0x133/0x335 drivers/acpi/acpica/extrace.c:203
RBP: ffff880191d0e780 R08: ffff8801b5cda180 R09: ffffed003982c2f0
 acpi_ds_begin_method_execution+0x45/0x7ff drivers/acpi/acpica/dsmethod.c:304
R10: ffffed003982c2f0 R11: ffff8801cc161787 R12: dffffc0000000000
 acpi_ps_execute_method+0x93/0x597 drivers/acpi/acpica/psxface.c:105
R13: ffff8801cc3191f0 R14: 0000000000000000 R15: ffff880191d0e598
 acpi_ns_evaluate+0x717/0x9bc drivers/acpi/acpica/nseval.c:204
FS:  00007f337c059700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
 acpi_evaluate_object+0x48c/0x8cf drivers/acpi/acpica/nsxfeval.c:354
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 acpi_evaluate_integer+0x129/0x280 drivers/acpi/utils.c:296
CR2: 0000000001e44fd0 CR3: 00000001c78b5000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 acpi_bus_get_status_handle+0x26/0xa0 drivers/acpi/bus.c:127
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 acpi_bus_type_and_status drivers/acpi/scan.c:1697 [inline]
 acpi_bus_check_add+0x3b5/0xb60 drivers/acpi/scan.c:1851
Call Trace:
 acpi_ns_walk_namespace+0x224/0x400 drivers/acpi/acpica/nswalk.c:237
 acpi_walk_namespace+0xf2/0x12c drivers/acpi/acpica/nsxfeval.c:606
 acpi_bus_scan+0x146/0x170 drivers/acpi/scan.c:2041
 acpi_scan_init+0x403/0x8fe drivers/acpi/scan.c:2198
 acpi_init+0x941/0xa19 drivers/acpi/bus.c:1284
 do_one_initcall+0x127/0x913 init/main.c:884
 do_initcall_level init/main.c:952 [inline]
 do_initcalls init/main.c:960 [inline]
 do_basic_setup init/main.c:978 [inline]
 kernel_init_freeable+0x49b/0x58e init/main.c:1135
 kernel_init+0x11/0x1b3 init/main.c:1061
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415

The buggy address belongs to the object at ffff8801d6917300
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 16 bytes inside of
 32-byte region [ffff8801d6917300, ffff8801d6917320)
 shrink_node+0x429/0x16a0 mm/vmscan.c:2736
The buggy address belongs to the page:
page:ffffea00075a45c0 count:1 mapcount:0 mapping:ffff8801da8001c0 index:0xffff8801d6917fc1
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea000760b788 ffffea0007597848 ffff8801da8001c0
raw: ffff8801d6917fc1 ffff8801d6917000 000000010000002b 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d6917200: 00 00 06 fc fc fc fc fc 00 00 06 fc fc fc fc fc
 ffff8801d6917280: 00 00 06 fc fc fc fc fc 00 00 06 fc fc fc fc fc
 shrink_zones mm/vmscan.c:2965 [inline]
 do_try_to_free_pages+0x3e7/0x1290 mm/vmscan.c:3027
>ffff8801d6917300: 00 00 06 fc fc fc fc fc 00 00 06 fc fc fc fc fc
                         ^
 ffff8801d6917380: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8801d6917400: 05 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc
==================================================================
 try_to_free_pages+0x4b2/0xb80 mm/vmscan.c:3242