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BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:188 [inline]
BUG: KASAN: use-after-free in list_empty include/linux/list.h:203 [inline]
BUG: KASAN: use-after-free in shrink_slab_memcg mm/vmscan.c:595 [inline]
BUG: KASAN: use-after-free in shrink_slab+0xa04/0xa60 mm/vmscan.c:671
Read of size 8 at addr ffff8801acb64858 by task syz-executor2/15450

CPU: 0 PID: 15450 Comm: syz-executor2 Not tainted 4.18.0-rc4-next-20180713+ #7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x30d mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 __read_once_size include/linux/compiler.h:188 [inline]
 list_empty include/linux/list.h:203 [inline]
 shrink_slab_memcg mm/vmscan.c:595 [inline]
 shrink_slab+0xa04/0xa60 mm/vmscan.c:671
 shrink_node+0x429/0x16a0 mm/vmscan.c:2735
 shrink_zones mm/vmscan.c:2964 [inline]
 do_try_to_free_pages+0x3e7/0x1290 mm/vmscan.c:3026
 try_to_free_mem_cgroup_pages+0x49d/0xc90 mm/vmscan.c:3324
 memory_high_write+0x283/0x310 mm/memcontrol.c:5611
 cgroup_file_write+0x31f/0x840 kernel/cgroup/cgroup.c:3502
 kernfs_fop_write+0x2ba/0x480 fs/kernfs/file.c:316
 __vfs_write+0x117/0x9d0 fs/read_write.c:485
 vfs_write+0x1fc/0x560 fs/read_write.c:549
 ksys_write+0x101/0x260 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455ab9
Code: 1d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007f2356d24c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f2356d256d4 RCX: 0000000000455ab9
RDX: 0000000000000001 RSI: 0000000020000000 RDI: 0000000000000017
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c2c77 R14: 00000000004d4c80 R15: 0000000000000000

Allocated by task 6592:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 __do_kmalloc_node mm/slab.c:3682 [inline]
 __kmalloc_node+0x47/0x70 mm/slab.c:3689
 kmalloc_node include/linux/slab.h:555 [inline]
 kvmalloc_node+0x65/0xf0 mm/util.c:423
 kvmalloc include/linux/mm.h:557 [inline]
 seq_buf_alloc fs/seq_file.c:32 [inline]
 seq_read+0x99b/0x1150 fs/seq_file.c:204
 kernfs_fop_read+0x146/0x6a0 fs/kernfs/file.c:252
 __vfs_read+0x117/0x9b0 fs/read_write.c:416
 vfs_read+0x17f/0x3c0 fs/read_write.c:452
 ksys_read+0x101/0x260 fs/read_write.c:578
 __do_sys_read fs/read_write.c:588 [inline]
 __se_sys_read fs/read_write.c:586 [inline]
 __x64_sys_read+0x73/0xb0 fs/read_write.c:586
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 6592:
 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
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xd9/0x260 mm/slab.c:3813
 kvfree+0x61/0x70 mm/util.c:442
 seq_release+0x51/0x80 fs/seq_file.c:359
 kernfs_fop_release+0xf7/0x1a0 fs/kernfs/file.c:781
 __fput+0x35d/0x930 fs/file_table.c:252
 ____fput+0x15/0x20 fs/file_table.c:288
 task_work_run+0x1ec/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801acb64100
 which belongs to the cache kmalloc-4096 of size 4096
The buggy address is located 1880 bytes inside of
 4096-byte region [ffff8801acb64100, ffff8801acb65100)
The buggy address belongs to the page:
page:ffffea0006b2d900 count:1 mapcount:0 mapping:ffff8801da800dc0 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffffea000657b408 ffffea0007648c88 ffff8801da800dc0
raw: 0000000000000000 ffff8801acb64100 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801acb64700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801acb64780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801acb64800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff8801acb64880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801acb64900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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