kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
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Modules linked in:
CPU: 0 PID: 3293 Comm: syz-executor4 Not tainted 4.14.0-rc7-next-20171103+ #10
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
task: ffff88006c7aa540 task.stack: ffff8800670a0000
RIP: 0010:asn1_ber_decoder+0x41e/0x1af0 lib/asn1_decoder.c:233
RSP: 0018:ffff8800670a78d0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffc900016d2000 RDI: ffffffff853f1920
RBP: ffff8800670a7b88 R08: 0000000000000060 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff8800670a7b60 R15: dffffc0000000000
FS:  00007f282cb09700(0000) GS:ffff88003ec00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020003000 CR3: 0000000021649000 CR4: 00000000000026f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 pkcs7_parse_message+0x2b3/0x730 crypto/asymmetric_keys/pkcs7_parser.c:139
 verify_pkcs7_signature+0x8d/0x290 certs/system_keyring.c:216
 pkcs7_preparse+0x7b/0xc0 crypto/asymmetric_keys/pkcs7_key_type.c:63
 key_create_or_update+0x533/0x1040 security/keys/key.c:855
 SYSC_add_key security/keys/keyctl.c:122 [inline]
 SyS_add_key+0x18a/0x340 security/keys/keyctl.c:62
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x447c89
RSP: 002b:00007f282cb08bd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8
RAX: ffffffffffffffda RBX: 00007f282cb096cc RCX: 0000000000447c89
RDX: 0000000020000000 RSI: 0000000020002000 RDI: 0000000020002ff5
RBP: 0000000000000086 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000005568 R14: 00000000006e9608 R15: 00007f282cb09700
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 
RIP: asn1_ber_decoder+0x41e/0x1af0 lib/asn1_decoder.c:233 RSP: ffff8800670a78d0
---[ end trace ae8de93e2d6f6421 ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
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Kernel Offset: disabled
Rebooting in 86400 seconds..