binder: undelivered TRANSACTION_ERROR: 29189
binder: undelivered TRANSACTION_ERROR: 29201
==================================================================
BUG: KASAN: use-after-free in pppol2tp_session_destruct+0xee/0x110 net/l2tp/l2tp_ppp.c:476
Read of size 4 at addr ffff8800bb315b80 by task syz-executor2/12422

CPU: 1 PID: 12422 Comm: syz-executor2 Not tainted 4.4.125-g38f41ec #21
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 3d65e3a14456a0b9 ffff8801bc9d7c20 ffffffff81d067bd
 ffffea0002ecc500 ffff8800bb315b80 0000000000000000 ffff8800bb315b80
 ffffffff82ded950 ffff8801bc9d7c58 ffffffff814fea83 ffff8800bb315b80
Call Trace:
 [<ffffffff81d067bd>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d067bd>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff814fea83>] print_address_description+0x73/0x260 mm/kasan/report.c:252
 [<ffffffff814fef95>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff814fef95>] kasan_report+0x285/0x370 mm/kasan/report.c:408
 [<ffffffff814ff0d4>] __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:428
 [<ffffffff8346b0ce>] pppol2tp_session_destruct+0xee/0x110 net/l2tp/l2tp_ppp.c:476
 [<ffffffff82e0285a>] sk_destruct+0x4a/0x4c0 net/core/sock.c:1447
 [<ffffffff82e02d27>] __sk_free+0x57/0x230 net/core/sock.c:1480
 [<ffffffff82e02f30>] sk_free+0x30/0x40 net/core/sock.c:1491
 [<ffffffff8346bf8a>] sock_put include/net/sock.h:1639 [inline]
 [<ffffffff8346bf8a>] pppol2tp_release+0x27a/0x310 net/l2tp/l2tp_ppp.c:518
 [<ffffffff82ded7fd>] sock_release+0x8d/0x1e0 net/socket.c:586
 [<ffffffff82ded966>] sock_close+0x16/0x20 net/socket.c:1037
 [<ffffffff81523f43>] __fput+0x233/0x6d0 fs/file_table.c:208
 [<ffffffff81524465>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8118bd44>] task_work_run+0x104/0x180 kernel/task_work.c:115
 [<ffffffff8100361d>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff8100361d>] exit_to_usermode_loop+0x13d/0x160 arch/x86/entry/common.c:252
 [<ffffffff81007084>] prepare_exit_to_usermode arch/x86/entry/common.c:283 [inline]
 [<ffffffff81007084>] syscall_return_slowpath arch/x86/entry/common.c:348 [inline]
 [<ffffffff81007084>] do_syscall_32_irqs_on arch/x86/entry/common.c:398 [inline]
 [<ffffffff81007084>] do_fast_syscall_32+0x614/0x8a0 arch/x86/entry/common.c:459
 [<ffffffff8377b2aa>] sysenter_flags_fixed+0xd/0x17

Allocated by task 12402:
 [<ffffffff81035d76>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fdaf3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fddbd>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fddbd>] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616
 [<ffffffff814fa0a4>] __kmalloc+0x124/0x320 mm/slub.c:3613
 [<ffffffff83464d89>] kmalloc include/linux/slab.h:481 [inline]
 [<ffffffff83464d89>] kzalloc include/linux/slab.h:620 [inline]
 [<ffffffff83464d89>] l2tp_session_create+0x39/0x10f0 net/l2tp/l2tp_core.c:1744
 [<ffffffff8346941c>] pppol2tp_connect+0x10fc/0x1930 net/l2tp/l2tp_ppp.c:718
 [<ffffffff82df21b6>] SYSC_connect+0x1b6/0x310 net/socket.c:1557
 [<ffffffff82df4a24>] SyS_connect+0x24/0x30 net/socket.c:1538
 [<ffffffff81006d91>] do_syscall_32_irqs_on arch/x86/entry/common.c:392 [inline]
 [<ffffffff81006d91>] do_fast_syscall_32+0x321/0x8a0 arch/x86/entry/common.c:459
 [<ffffffff8377b2aa>] sysenter_flags_fixed+0xd/0x17

Freed by task 12402:
 [<ffffffff81035d76>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fdaf3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fe412>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fe412>] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:589
 [<ffffffff814faeac>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff814faeac>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff814faeac>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff814faeac>] kfree+0xfc/0x300 mm/slub.c:3749
 [<ffffffff83461310>] l2tp_session_free+0x170/0x200 net/l2tp/l2tp_core.c:1672
 [<ffffffff83463bc1>] l2tp_session_dec_refcount_1 net/l2tp/l2tp_core.h:293 [inline]
 [<ffffffff83463bc1>] l2tp_tunnel_closeall+0x2d1/0x3b0 net/l2tp/l2tp_core.c:1279
 [<ffffffff8346472b>] l2tp_udp_encap_destroy+0x8b/0xf0 net/l2tp/l2tp_core.c:1300
 [<ffffffff833729c1>] udpv6_destroy_sock+0xb1/0xd0 net/ipv6/udp.c:1421
 [<ffffffff82e048fb>] sk_common_release+0x6b/0x300 net/core/sock.c:2680
 [<ffffffff83371975>] udp_lib_close+0x15/0x20 include/net/udp.h:190
 [<ffffffff831d5eba>] inet_release+0xfa/0x1d0 net/ipv4/af_inet.c:435
 [<ffffffff832fb320>] inet6_release+0x50/0x70 net/ipv6/af_inet6.c:424
 [<ffffffff82ded7fd>] sock_release+0x8d/0x1e0 net/socket.c:586
 [<ffffffff82ded966>] sock_close+0x16/0x20 net/socket.c:1037
 [<ffffffff81523f43>] __fput+0x233/0x6d0 fs/file_table.c:208
 [<ffffffff81524465>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8118bd44>] task_work_run+0x104/0x180 kernel/task_work.c:115
 [<ffffffff8100361d>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff8100361d>] exit_to_usermode_loop+0x13d/0x160 arch/x86/entry/common.c:252
 [<ffffffff81007084>] prepare_exit_to_usermode arch/x86/entry/common.c:283 [inline]
 [<ffffffff81007084>] syscall_return_slowpath arch/x86/entry/common.c:348 [inline]
 [<ffffffff81007084>] do_syscall_32_irqs_on arch/x86/entry/common.c:398 [inline]
 [<ffffffff81007084>] do_fast_syscall_32+0x614/0x8a0 arch/x86/entry/common.c:459
 [<ffffffff8377b2aa>] sysenter_flags_fixed+0xd/0x17

The buggy address belongs to the object at ffff8800bb315b80
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 0 bytes inside of
 512-byte region [ffff8800bb315b80, ffff8800bb315d80)
The buggy address belongs to the page:
BUG: unable to handle kernel paging request at fffff240005d99bb
IP: [<ffffffff814a1055>] pmd_offset arch/x86/include/asm/pgtable.h:612 [inline]
IP: [<ffffffff814a1055>] pmd_alloc include/linux/mm.h:1486 [inline]
IP: [<ffffffff814a1055>] __handle_mm_fault mm/memory.c:3357 [inline]
IP: [<ffffffff814a1055>] handle_mm_fault+0x2c5/0x3190 mm/memory.c:3455
PGD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 12397 Comm: syz-executor6 Not tainted 4.4.125-g38f41ec #21
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d9b8c800 task.stack: ffff8801bcd38000
RIP: 0010:[<ffffffff814a1055>]  [<ffffffff814a1055>] pmd_offset arch/x86/include/asm/pgtable.h:612 [inline]
RIP: 0010:[<ffffffff814a1055>]  [<ffffffff814a1055>] pmd_alloc include/linux/mm.h:1486 [inline]
RIP: 0010:[<ffffffff814a1055>]  [<ffffffff814a1055>] __handle_mm_fault mm/memory.c:3357 [inline]
RIP: 0010:[<ffffffff814a1055>]  [<ffffffff814a1055>] handle_mm_fault+0x2c5/0x3190 mm/memory.c:3455
RSP: 0000:ffff8801bcd3fd60  EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: 1ffff100379a7fbb RCX: ffffffff814a102f
RDX: 1ffff640005d99bb RSI: ffff8801d49da9b0 RDI: ffffea0002ecc500
RBP: ffff8801bcd3fec0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 1ffff100379a7fa2 R12: ffff880000000dd8
R13: 00002a0002ecc000 R14: ffffb20002eccdd8 R15: ffff8801d49da9b0
FS:  0000000000000000(0000) GS:ffff8801db200000(0063) knlGS:0000000009efd900
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: fffff240005d99bb CR3: 00000001cfc40000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 0000306d00000000 ffffffff8377746b 636578652d7a7973 006d0036726f7475
 0000000000000000 1ffff100379a7fb5 ffff8801bcd3fe68 ffff8801bcd3fdc8
 ffffffff813029e1 ffff8801bcd40000 ffff8801d49daa00 ffff880100000054
Call Trace:
 [<ffffffff810dc82b>] __do_page_fault+0x35b/0xa00 arch/x86/mm/fault.c:1245
 [<ffffffff810dcef7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1308
 [<ffffffff8377ad48>] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1037
Code: e8 51 06 ec ff 48 b8 00 00 00 00 00 fc ff df 4d 21 f5 49 be 00 00 00 00 00 88 ff ff 4d 01 f4 4f 8d 74 25 00 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 f9 29 00 00 4d 8b 26 4d 85 e4 75 72 e8 14 06 
RIP  [<ffffffff814a1055>] pmd_offset arch/x86/include/asm/pgtable.h:612 [inline]
RIP  [<ffffffff814a1055>] pmd_alloc include/linux/mm.h:1486 [inline]
RIP  [<ffffffff814a1055>] __handle_mm_fault mm/memory.c:3357 [inline]
RIP  [<ffffffff814a1055>] handle_mm_fault+0x2c5/0x3190 mm/memory.c:3455
 RSP <ffff8801bcd3fd60>
CR2: fffff240005d99bb
---[ end trace f77874778d5a715b ]---