IPVS: Creating netns size=2552 id=8
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 kernel/locking/lockdep.c:3092
Read of size 8 at addr ffff8801cdcca2a0 by task syz-executor5/4737

CPU: 1 PID: 4737 Comm: syz-executor5 Not tainted 4.4.112-g3fc4284 #25
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 b6f100aeb3596d82 ffff8801ce0bf550 ffffffff81d054ed
 ffffea0007373200 ffff8801cdcca2a0 0000000000000000 ffff8801cdcca2a0
 0000000000000000 ffff8801ce0bf588 ffffffff814fd953 ffff8801cdcca2a0
Call Trace:
 [<ffffffff81d054ed>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d054ed>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff814fd953>] print_address_description+0x73/0x260 mm/kasan/report.c:252
 [<ffffffff814fde65>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff814fde65>] kasan_report+0x285/0x370 mm/kasan/report.c:408
 [<ffffffff814fdfc4>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:429
 [<ffffffff81239c7e>] __lock_acquire+0x387e/0x4b50 kernel/locking/lockdep.c:3092
 [<ffffffff8123c7be>] lock_acquire+0x15e/0x460 kernel/locking/lockdep.c:3592
 [<ffffffff837754aa>] __raw_spin_lock_bh include/linux/spinlock_api_smp.h:137 [inline]
 [<ffffffff837754aa>] _raw_spin_lock_bh+0x3a/0x50 kernel/locking/spinlock.c:175
 [<ffffffff82df6aa3>] spin_lock_bh include/linux/spinlock.h:307 [inline]
 [<ffffffff82df6aa3>] lock_sock_nested+0x43/0x120 net/core/sock.c:2451
 [<ffffffff834674a0>] lock_sock include/net/sock.h:1493 [inline]
 [<ffffffff834674a0>] pppol2tp_release+0x50/0x310 net/l2tp/l2tp_ppp.c:493
 [<ffffffff82dea37d>] sock_release+0x8d/0x1e0 net/socket.c:586
 [<ffffffff82dea4e6>] sock_close+0x16/0x20 net/socket.c:1037
 [<ffffffff81522f93>] __fput+0x233/0x6d0 fs/file_table.c:208
 [<ffffffff815234b5>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8118bb54>] task_work_run+0x104/0x180 kernel/task_work.c:115
 [<ffffffff81132f21>] exit_task_work include/linux/task_work.h:21 [inline]
 [<ffffffff81132f21>] do_exit+0x871/0x2a20 kernel/exit.c:755
 [<ffffffff81139398>] do_group_exit+0x108/0x320 kernel/exit.c:885
 [<ffffffff8115c895>] get_signal+0x565/0x1660 kernel/signal.c:2317
 [<ffffffff8100e7fb>] do_signal+0x8b/0x1d40 arch/x86/kernel/signal.c:712
 [<ffffffff81003602>] exit_to_usermode_loop+0x122/0x170 arch/x86/entry/common.c:247
 [<ffffffff81007077>] prepare_exit_to_usermode arch/x86/entry/common.c:282 [inline]
 [<ffffffff81007077>] syscall_return_slowpath arch/x86/entry/common.c:347 [inline]
 [<ffffffff81007077>] do_syscall_32_irqs_on arch/x86/entry/common.c:396 [inline]
 [<ffffffff81007077>] do_fast_syscall_32+0x607/0x890 arch/x86/entry/common.c:457
 [<ffffffff83777b6a>] sysenter_flags_fixed+0xd/0x17

Allocated by task 4746:
 [<ffffffff81035df6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fc9c3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fcc8d>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fcc8d>] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616
 [<ffffffff814f8f64>] __kmalloc+0x124/0x320 mm/slub.c:3613
 [<ffffffff82df58bc>] kmalloc include/linux/slab.h:481 [inline]
 [<ffffffff82df58bc>] sk_prot_alloc+0x18c/0x310 net/core/sock.c:1354
 [<ffffffff82dfbc0a>] sk_alloc+0x3a/0x3a0 net/core/sock.c:1419
 [<ffffffff83463283>] pppol2tp_create+0x33/0x1f0 net/l2tp/l2tp_ppp.c:551
 [<ffffffff827ffe61>] pppox_create+0xf1/0x200 drivers/net/ppp/pppox.c:121
 [<ffffffff82df07ec>] __sock_create+0x3ac/0x640 net/socket.c:1177
 [<ffffffff82df0cb0>] sock_create net/socket.c:1217 [inline]
 [<ffffffff82df0cb0>] SYSC_socket net/socket.c:1247 [inline]
 [<ffffffff82df0cb0>] SyS_socket+0xf0/0x1b0 net/socket.c:1227
 [<ffffffff81006d84>] do_syscall_32_irqs_on arch/x86/entry/common.c:390 [inline]
 [<ffffffff81006d84>] do_fast_syscall_32+0x314/0x890 arch/x86/entry/common.c:457
 [<ffffffff83777b6a>] sysenter_flags_fixed+0xd/0x17

Freed by task 4737:
 [<ffffffff81035df6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fc9c3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fd2e2>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fd2e2>] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:589
 [<ffffffff814f9d6c>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff814f9d6c>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff814f9d6c>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff814f9d6c>] kfree+0xfc/0x300 mm/slub.c:3749
 [<ffffffff82dff7d7>] sk_prot_free net/core/sock.c:1391 [inline]
 [<ffffffff82dff7d7>] sk_destruct+0x3f7/0x4c0 net/core/sock.c:1472
 [<ffffffff82dff8f7>] __sk_free+0x57/0x230 net/core/sock.c:1480
 [<ffffffff82dffb00>] sk_free+0x30/0x40 net/core/sock.c:1491
 [<ffffffff8346688f>] sock_put include/net/sock.h:1639 [inline]
 [<ffffffff8346688f>] pppol2tp_session_sock_put+0x5f/0x70 net/l2tp/l2tp_ppp.c:286
 [<ffffffff8345f284>] l2tp_tunnel_closeall+0x254/0x3b0 net/l2tp/l2tp_core.c:1277
 [<ffffffff8345fe6b>] l2tp_udp_encap_destroy+0x8b/0xf0 net/l2tp/l2tp_core.c:1300
 [<ffffffff8336e6b1>] udpv6_destroy_sock+0xb1/0xd0 net/ipv6/udp.c:1421
 [<ffffffff82e014cb>] sk_common_release+0x6b/0x300 net/core/sock.c:2680
 [<ffffffff8336d665>] udp_lib_close+0x15/0x20 include/net/udp.h:190
 [<ffffffff831d16da>] inet_release+0xfa/0x1d0 net/ipv4/af_inet.c:435
 [<ffffffff832f6f90>] inet6_release+0x50/0x70 net/ipv6/af_inet6.c:424
 [<ffffffff82dea37d>] sock_release+0x8d/0x1e0 net/socket.c:586
 [<ffffffff82dea4e6>] sock_close+0x16/0x20 net/socket.c:1037
 [<ffffffff81522f93>] __fput+0x233/0x6d0 fs/file_table.c:208
 [<ffffffff815234b5>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8118bb54>] task_work_run+0x104/0x180 kernel/task_work.c:115
 [<ffffffff81003625>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff81003625>] exit_to_usermode_loop+0x145/0x170 arch/x86/entry/common.c:251
 [<ffffffff81007077>] prepare_exit_to_usermode arch/x86/entry/common.c:282 [inline]
 [<ffffffff81007077>] syscall_return_slowpath arch/x86/entry/common.c:347 [inline]
 [<ffffffff81007077>] do_syscall_32_irqs_on arch/x86/entry/common.c:396 [inline]
 [<ffffffff81007077>] do_fast_syscall_32+0x607/0x890 arch/x86/entry/common.c:457
 [<ffffffff83777b6a>] sysenter_flags_fixed+0xd/0x17

The buggy address belongs to the object at ffff8801cdcca200
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 160 bytes inside of
 2048-byte region [ffff8801cdcca200, ffff8801cdccaa00)
The buggy address belongs to the page:
PANIC: double fault, error_code: 0x0
CPU: 1 PID: 4737 Comm: syz-executor5 Not tainted 4.4.112-g3fc4284 #25
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801ce37af80 task.stack: ffff8801ce0b8000
RIP: 0010:[<ffffffff8148fd3a>]  [<ffffffff8148fd3a>] dump_page_badflags+0x1a/0x250 mm/debug.c:84
RSP: 0018:ffff880100000000  EFLAGS: 00010086
RAX: ffff8801ce37af80 RBX: ffffea0007373200 RCX: ffffffff8148fea0
RDX: 0000000000000000 RSI: ffffffff838a8620 RDI: ffffea0007373200
RBP: ffff880100000030 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000002 R11: fffffbfff0ad7a1e R12: 0000000000000000
R13: ffffffff838a8620 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: ffff8800fffffff8 CR3: 000000000420c000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:

Call Trace:
 <UNK> 
Code: e2 06 00 e9 1d fd ff ff 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 56 41 55 49 89 f5 41 54 49 89 d4 53 48 89 fb 48 83 ec 08 <e8> 11 01 ed ff 48 8d 7b 10 48 b8 00 00 00 00 00 fc ff df 48 89