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: 2990 Comm: syzkaller888396 Not tainted 4.14.0-rc7-next-20171103+ #38
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d07364c0 task.stack: ffff8801ce7c8000
RIP: 0010:asn1_ber_decoder+0x41e/0x1af0 lib/asn1_decoder.c:233
RSP: 0018:ffff8801ce7cf8d0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8801ce96b780 RDI: ffffffff853f1920
RBP: ffff8801ce7cfb88 R08: 0000000000000060 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff8801ce7cfb60 R15: dffffc0000000000
FS:  0000000000d81880(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000207c9ffb CR3: 00000001bf317000 CR4: 00000000001406f0
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: 0033:0x43fcd9
RSP: 002b:00007fffcb8c1408 EFLAGS: 00000217 ORIG_RAX: 00000000000000f8
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fcd9
RDX: 0000000020000000 RSI: 00000000207c9ffb RDI: 000000002009b000
RBP: 0000000000000086 R08: fffffffffffffffe R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000401640
R13: 00000000004016d0 R14: 0000000000000000 R15: 0000000000000000
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: ffff8801ce7cf8d0
---[ end trace 2b5d6af98bc7933f ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
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Kernel Offset: disabled
Rebooting in 86400 seconds..