==================================================================
BUG: KASAN: use-after-free in l2tp_session_queue_purge+0xf4/0x100 net/l2tp/l2tp_core.c:830
Read of size 4 at addr ffff8800b1e5af00 by task syz-executor3/12040

CPU: 0 PID: 12040 Comm: syz-executor3 Not tainted 4.4.153-g5e24b4e #90
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 e518674481d94e0c ffff8800b90dfcb8 ffffffff81e162ed
 ffffea0002c79680 ffff8800b1e5af00 0000000000000000 ffff8800b1e5af00
 0000000000000000 ffff8800b90dfcf0 ffffffff8151b4d9 ffff8800b1e5af00
Call Trace:
 [<ffffffff81e162ed>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81e162ed>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff8151b4d9>] print_address_description+0x6c/0x216 mm/kasan/report.c:252
 [<ffffffff8151b7f8>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8151b7f8>] kasan_report.cold.7+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff814fe764>] __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:428
 [<ffffffff835a4e64>] l2tp_session_queue_purge+0xf4/0x100 net/l2tp/l2tp_core.c:830
 [<ffffffff835b196f>] pppol2tp_release+0x1ff/0x310 net/l2tp/l2tp_ppp.c:509
 [<ffffffff82f213c9>] __sock_release+0xd9/0x260 net/socket.c:592
 [<ffffffff82f21569>] sock_close+0x19/0x20 net/socket.c:1050
 [<ffffffff815288c5>] __fput+0x235/0x6f0 fs/file_table.c:208
 [<ffffffff81528e05>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8118ee9f>] task_work_run+0x10f/0x190 kernel/task_work.c:115
 [<ffffffff8100362d>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff8100362d>] exit_to_usermode_loop+0x13d/0x160 arch/x86/entry/common.c:253
 [<ffffffff81006535>] prepare_exit_to_usermode arch/x86/entry/common.c:284 [inline]
 [<ffffffff81006535>] syscall_return_slowpath+0x1b5/0x1f0 arch/x86/entry/common.c:349
 [<ffffffff838cc9f5>] int_ret_from_sys_call+0x25/0xa3

Allocated by task 12050:
 [<ffffffff81034676>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fd823>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fdb07>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fdb07>] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:616
 [<ffffffff814fa244>] __kmalloc+0x124/0x310 mm/slub.c:3613
 [<ffffffff835aa279>] kmalloc include/linux/slab.h:481 [inline]
 [<ffffffff835aa279>] kzalloc include/linux/slab.h:620 [inline]
 [<ffffffff835aa279>] l2tp_session_create+0x39/0x1030 net/l2tp/l2tp_core.c:1748
 [<ffffffff835aef80>] pppol2tp_connect+0x10f0/0x1910 net/l2tp/l2tp_ppp.c:725
 [<ffffffff82f27ef8>] SYSC_connect+0x1b8/0x300 net/socket.c:1570
 [<ffffffff82f2a844>] SyS_connect+0x24/0x30 net/socket.c:1551
 [<ffffffff838cc865>] entry_SYSCALL_64_fastpath+0x22/0x9e

Freed by task 12058:
 [<ffffffff81034676>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fd823>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fe152>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fe152>] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:589
 [<ffffffff814fb6b4>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff814fb6b4>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff814fb6b4>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff814fb6b4>] kfree+0xf4/0x310 mm/slub.c:3749
 [<ffffffff835a71e0>] l2tp_session_free+0x170/0x200 net/l2tp/l2tp_core.c:1676
 [<ffffffff835a9599>] l2tp_session_dec_refcount_1 net/l2tp/l2tp_core.h:293 [inline]
 [<ffffffff835a9599>] l2tp_tunnel_closeall+0x2b9/0x350 net/l2tp/l2tp_core.c:1279
 [<ffffffff835aa0ab>] l2tp_udp_encap_destroy+0x8b/0xf0 net/l2tp/l2tp_core.c:1300
 [<ffffffff8349bf11>] udpv6_destroy_sock+0xb1/0xd0 net/ipv6/udp.c:1421
 [<ffffffff82f38ddd>] sk_common_release+0x6d/0x300 net/core/sock.c:2680
 [<ffffffff8349abc5>] udp_lib_close+0x15/0x20 include/net/udp.h:190
 [<ffffffff8330274f>] inet_release+0xff/0x1d0 net/ipv4/af_inet.c:435
 [<ffffffff834251c0>] inet6_release+0x50/0x70 net/ipv6/af_inet6.c:424
 [<ffffffff82f213c9>] __sock_release+0xd9/0x260 net/socket.c:592
 [<ffffffff82f21569>] sock_close+0x19/0x20 net/socket.c:1050
 [<ffffffff815288c5>] __fput+0x235/0x6f0 fs/file_table.c:208
 [<ffffffff81528e05>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8118ee9f>] task_work_run+0x10f/0x190 kernel/task_work.c:115
 [<ffffffff8100362d>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff8100362d>] exit_to_usermode_loop+0x13d/0x160 arch/x86/entry/common.c:253
 [<ffffffff81006535>] prepare_exit_to_usermode arch/x86/entry/common.c:284 [inline]
 [<ffffffff81006535>] syscall_return_slowpath+0x1b5/0x1f0 arch/x86/entry/common.c:349
 [<ffffffff838cc9f5>] int_ret_from_sys_call+0x25/0xa3

The buggy address belongs to the object at ffff8800b1e5af00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 0 bytes inside of
 512-byte region [ffff8800b1e5af00, ffff8800b1e5b100)
The buggy address belongs to the page:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 12066 Comm: blkid Not tainted 4.4.153-g5e24b4e #90
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801bbe6b000 task.stack: ffff8800a51e0000
RIP: 0010:[<ffffffff81e78eb6>]  [<ffffffff81e78eb6>] __debug_check_no_obj_freed lib/debugobjects.c:689 [inline]
RIP: 0010:[<ffffffff81e78eb6>]  [<ffffffff81e78eb6>] debug_check_no_obj_freed+0x1a6/0x940 lib/debugobjects.c:726
RSP: 0018:ffff8800a51e7908  EFLAGS: 00010803
RAX: 0000000000000282 RBX: e4afe8df89480b0f RCX: 0000000000000000
RDX: 1c95fd1bf1290161 RSI: 0000000000000002 RDI: ffffffff[  230.682894] kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#2] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 12066 Comm: blkid Not tainted 4.4.153-g5e24b4e #90
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801bbe6b000 task.stack: ffff8800a51e0000
RIP: 0010:[<ffffffff81490290>]  [<ffffffff81490290>] constant_test_bit arch/x86/include/asm/bitops.h:311 [inline]
RIP: 0010:[<ffffffff81490290>]  [<ffffffff81490290>] PageSlab include/linux/page-flags.h:217 [inline]
RIP: 0010:[<ffffffff81490290>]  [<ffffffff81490290>] page_mapcount include/linux/mm.h:464 [inline]
RIP: 0010:[<ffffffff81490290>]  [<ffffffff81490290>] dump_page_badflags+0x30/0x70 mm/debug.c:85
RSP: 0018:ffff8800a51e7228  EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 0000007ceb131d30 RCX: 0000000000000001
RDX: 0000000f9d6263a6 RSI: ffffffff81e75e5b RDI: ffffffff85931780
RBP: ffff8800a51e7258 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff858f028f R12: 0000007ceb131c6a
R13: 00000000000008fd R14: 0000000000000001 R15: fffffbfff0c55ad1
FS:  00007f4ab8094740(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000079b1a0 CR3: 00000000b9aef000 CR4: 00000000001606f0
Stack:
 ffffffff862ad640 ffffea0002c79680 0000000000000000 ffffffff83aaae60
 ffff8800b1e5af00 ffff8800b1e5b100 ffff8800a51e7298 ffffffff814902b7
 ffffffff81e3ee75 ffffea0002c79680 0000000000000000 ffffffff83aaae60
Call Trace:
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
 [<ffffffff814902b7>] dump_page mm/debug.c:105 [inline]
 [<ffffffff814902b7>] page_mapcount include/linux/mm.h:464 [inline]
 [<ffffffff814902b7>] dump_page_badflags+0x57/0x70 mm/debug.c:85
Code: 57 41 56 41 55 49 89 f5 41 54 49 89 d4 53 48 89 fb 48 83 ec 08 e8 11 43 ec ff 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 75 23 48 8b 03 a8 80 0f 84 d6 91 08 00 e8 ea 42 ec 
RIP  [<ffffffff81490290>] constant_test_bit arch/x86/include/asm/bitops.h:311 [inline]
RIP  [<ffffffff81490290>] PageSlab include/linux/page-flags.h:217 [inline]
RIP  [<ffffffff81490290>] page_mapcount include/linux/mm.h:464 [inline]
RIP  [<ffffffff81490290>] dump_page_badflags+0x30/0x70 mm/debug.c:85
 RSP <ffff8800a51e7228>
---[ end trace 02209c041ab64dcc ]---