9pnet_virtio: no channels available for device ./file0/file0
==================================================================
netlink: 4 bytes leftover after parsing attributes in process `syz-executor1'.
tc_dump_action: action bad kind
BUG: KASAN: slab-out-of-bounds in asn1_ber_decoder+0x1436/0x1c20 lib/asn1_decoder.c:233
Read of size 1 at addr ffff8801d98d0ac2 by task syz-executor7/18758

CPU: 0 PID: 18758 Comm: syz-executor7 Not tainted 4.14.0-rc5-mm1+ #20
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 print_address_description+0x73/0x250 mm/kasan/report.c:252
9pnet_virtio: no channels available for device ./file0/file0
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:427
 asn1_ber_decoder+0x1436/0x1c20 lib/asn1_decoder.c:233
 x509_cert_parse+0x1dd/0x680 crypto/asymmetric_keys/x509_cert_parser.c:89
 x509_key_preparse+0x64/0x8b0 crypto/asymmetric_keys/x509_public_key.c:174
 asymmetric_key_preparse+0xa8/0x110 crypto/asymmetric_keys/asymmetric_type.c:386
 key_create_or_update+0x4c6/0xe20 security/keys/key.c:846
 SYSC_add_key security/keys/keyctl.c:122 [inline]
 SyS_add_key+0x18a/0x340 security/keys/keyctl.c:62
 do_syscall_64+0x26c/0x8d0 arch/x86/entry/common.c:287
 entry_SYSCALL64_slow_path+0x25/0x25
RIP: 0033:0x452869
RSP: 002b:00007f0086bb5be8 EFLAGS: 00000212 ORIG_RAX: 00000000000000f8
RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452869
RDX: 0000000020ce1000 RSI: 0000000020819000 RDI: 0000000020b79000
RBP: 0000000000000014 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000212 R12: 00000000006ee280
R13: 00000000ffffffff R14: 00007f0086bb66d4 R15: 0000000000000000

Allocated by task 18758:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 __do_kmalloc_node mm/slab.c:3676 [inline]
 __kmalloc_node+0x47/0x70 mm/slab.c:3683
 kmalloc_node include/linux/slab.h:541 [inline]
 kvmalloc_node+0x99/0xd0 mm/util.c:397
 kvmalloc include/linux/mm.h:538 [inline]
 SYSC_add_key security/keys/keyctl.c:104 [inline]
 SyS_add_key+0x279/0x340 security/keys/keyctl.c:62
 do_syscall_64+0x26c/0x8d0 arch/x86/entry/common.c:287
 return_from_SYSCALL_64+0x0/0x7a

Freed by task 16613:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3492 [inline]
 kfree+0xca/0x250 mm/slab.c:3807
 kvfree+0x36/0x60 mm/util.c:416
 kvm_arch_free_memslot+0x85/0x230 arch/x86/kvm/x86.c:8279
 kvm_free_memslot+0xb8/0x110 arch/x86/kvm/../../../virt/kvm/kvm_main.c:529
 kvm_free_memslots+0x9d/0xd0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:542
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:730 [inline]
 kvm_put_kvm+0x916/0xde0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:748
 kvm_vm_release+0x42/0x50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:759
 __fput+0x327/0x7e0 fs/file_table.c:210
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x199/0x270 kernel/task_work.c:112
 exit_task_work include/linux/task_work.h:21 [inline]
 do_exit+0x9b5/0x1ad0 kernel/exit.c:869
 do_group_exit+0x149/0x400 kernel/exit.c:972
 get_signal+0x73f/0x16d0 kernel/signal.c:2333
 do_signal+0x94/0x1ee0 arch/x86/kernel/signal.c:808
 exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath+0x42f/0x510 arch/x86/entry/common.c:266
 entry_SYSCALL_64_fastpath+0xbc/0xbe

The buggy address belongs to the object at ffff8801d98d0ac0
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 2 bytes inside of
 32-byte region [ffff8801d98d0ac0, ffff8801d98d0ae0)
The buggy address belongs to the page:
page:ffffea0007663400 count:1 mapcount:0 mapping:ffff8801d98d0000 index:0xffff8801d98d0fc1
flags: 0x200000000000100(slab)
raw: 0200000000000100 ffff8801d98d0000 ffff8801d98d0fc1 000000010000003e
raw: ffffea0007665a20 ffffea000743ae20 ffff8801dac001c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d98d0980: fb fb fb fb fc fc fc fc 07 fc fc fc fc fc fc fc
 ffff8801d98d0a00: 07 fc fc fc fc fc fc fc 07 fc fc fc fc fc fc fc
>ffff8801d98d0a80: 00 00 00 00 fc fc fc fc 02 fc fc fc fc fc fc fc
                                           ^
 ffff8801d98d0b00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8801d98d0b80: fb fb fb fb fc fc fc fc 00 04 fc fc fc fc fc fc
==================================================================