syzkaller login: [   24.094373] kasan: CONFIG_KASAN_INLINE enabled
[   24.094979] kasan: GPF could be caused by NULL-ptr deref or user memory access
[   24.095920] general protection fault: 0000 [#1] SMP KASAN
[   24.096491] Dumping ftrace buffer:
[   24.096829]    (ftrace buffer empty)
[   24.099850] Modules linked in:
[   24.100302] CPU: 3 PID: 3021 Comm: syzkaller838500 Not tainted 4.14.0-rc7-next-20171103+ #10
[   24.101501] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
[   24.102723] task: ffff88003b640080 task.stack: ffff8800388c8000
[   24.103566] RIP: 0010:asn1_ber_decoder+0x41e/0x1af0
executing program
[   24.104230] RSP: 0018:ffff8800388cf8d0 EFLAGS: 00010246
[   24.106044] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   24.106798] RDX: 0000000000000000 RSI: ffff88006b104240 RDI: ffffffff853f1920
[   24.107510] RBP: ffff8800388cfb88 R08: 0000000000000060 R09: 0000000000000000
[   24.108223] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[   24.108932] R13: 0000000000000000 R14: ffff8800388cfb60 R15: dffffc0000000000
[   24.110086] FS:  0000000000f33880(0000) GS:ffff88006df00000(0000) knlGS:0000000000000000
[   24.110952] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   24.111531] CR2: 0000000020e5d000 CR3: 0000000067627000 CR4: 00000000000006e0
[   24.112299] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   24.113175] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   24.113970] Call Trace:
[   24.114234]  ? pkcs7_parse_message+0x18a/0x730
[   24.114684]  ? verify_pkcs7_signature+0x8d/0x290
[   24.115161]  ? pkcs7_preparse+0x7b/0xc0
[   24.115563]  ? depot_save_stack+0x490/0x490
[   24.116002]  ? __lock_is_held+0xbc/0x140
[   24.116416]  ? __lock_is_held+0xbc/0x140
[   24.116829]  ? pkcs7_parse_message+0x18a/0x730
[   24.117481]  ? rcu_read_lock_sched_held+0x108/0x120
[   24.118008]  ? kmem_cache_alloc_trace+0x459/0x750
[   24.118482]  ? lock_release+0xd70/0xd70
[   24.118885]  pkcs7_parse_message+0x2b3/0x730
[   24.119336]  ? key_task_permission+0x330/0x330
[   24.119800]  ? pkcs7_supply_detached_data+0x90/0x90
[   24.120306]  verify_pkcs7_signature+0x8d/0x290
[   24.120765]  ? restrict_link_by_builtin_and_secondary_trusted+0x80/0x80
[   24.121603]  ? __down_interruptible+0x6b0/0x6b0
[   24.122144]  ? trace_hardirqs_on+0xd/0x10
[   24.122562]  ? current_kernel_time64+0x1d4/0x2f0
[   24.123043]  ? pkcs7_supply_detached_data+0x90/0x90
[   24.123543]  pkcs7_preparse+0x7b/0xc0
[   24.123936]  ? pkcs7_preparse+0xc0/0xc0
[   24.124340]  key_create_or_update+0x533/0x1040
[   24.124801]  ? key_type_lookup+0xd0/0xd0
[   24.125421]  ? join_session_keyring+0x300/0x300
[   24.125989]  ? mem_cgroup_commit_charge+0x111/0x750
[   24.126593]  ? memdup_user+0x5e/0x90
[   24.126973]  SyS_add_key+0x18a/0x340
[   24.127341]  ? key_get_type_from_user.constprop.10+0xd0/0xd0
[   24.127923]  ? trace_hardirqs_on_caller+0x421/0x5c0
[   24.128426]  entry_SYSCALL_64_fastpath+0x1f/0xbe
[   24.128905] RIP: 0033:0x434e89
[   24.129273] RSP: 002b:00007ffea35d1d48 EFLAGS: 00000217 ORIG_RAX: 00000000000000f8
[   24.130273] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000434e89
[   24.130996] RDX: 0000000020000000 RSI: 0000000020bc4ffb RDI: 0000000020e5cff5
[   24.131716] RBP: 0000000000000086 R08: ffffffffffffffff R09: 0000000000000000
[   24.132436] R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000000000
[   24.133289] R13: 0000000000401800 R14: 0000000000401890 R15: 0000000000000000
[   24.134156] Code: 19 ff 48 8d 43 01 49 89 86 80 fe ff ff 48 89 85 a8 fd ff ff 48 8b 85 c0 fd ff ff 48 01 d8 48 89 c2 48 89 c1 48 c1 ea 03 83 e1 07 <42> 0f b6 14 3a 38 ca 7f 08 84 d2 0f 85 cd 0f 00 00 0f b6 00 88 
[   24.136195] RIP: asn1_ber_decoder+0x41e/0x1af0 RSP: ffff8800388cf8d0
[   24.136967] ---[ end trace 0a72b69eb7f3b073 ]---
[   24.138349] Kernel panic - not syncing: Fatal exception
[   24.141112] Dumping ftrace buffer:
[   24.141584]    (ftrace buffer empty)
[   24.142035] Kernel Offset: disabled
[   24.142477] Rebooting in 86400 seconds..