Hello,

syzkaller hit the following crash on  
1ea8d039f9edcfefb20d8ddfe136930f6e551529
git://git.cmpxchg.org/linux-mmots.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See https://goo.gl/kgGztJ
for information about syzkaller reproducers


kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 25985 Comm: cryptomgr_test Not tainted 4.14.0-mm1+ #25
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
task: ffff8801c4562180 task.stack: ffff8801d5b70000
RIP: 0010:crypto_remove_spawns+0x58c/0x1260 crypto/algapi.c:159
RSP: 0018:ffff8801d5b779e8 EFLAGS: 00010206
RAX: 0000000000000003 RBX: dffffc0000000000 RCX: ffffffff82258aab
RDX: 0000000000000000 RSI: 1ffff1003ab6efa6 RDI: 0000000000000018
RBP: ffff8801d5b77dd8 R08: ffff8801d5b77d70 R09: 0000000000000004
R10: 0000000000000000 R11: ffffffff8747dda0 R12: 0000000000000000
R13: ffff8801c505bb60 R14: ffffed003ab6ef4e R15: ffff8801d5b77db0
FS:  0000000000000000(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff1d3ffcac CR3: 00000001cf825000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  crypto_alg_tested+0x514/0x6f0 crypto/algapi.c:311
  cryptomgr_test+0x17/0x30 crypto/algboss.c:226
  kthread+0x37a/0x440 kernel/kthread.c:238
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:437
Code: 84 e3 01 00 00 e8 35 94 4a ff 4c 89 e8 48 c1 e8 03 80 3c 18 00 0f 85  
d8 09 00 00 4d 8b 65 00 49 8d 7c 24 18 48 89 f8 48 c1 e8 03 <80> 3c 18 00  
0f 85 b4 09 00 00 4d 8b 6c 24 18 4c 3b ad 50 fc ff
RIP: crypto_remove_spawns+0x58c/0x1260 crypto/algapi.c:159 RSP:  
ffff8801d5b779e8
---[ end trace 14ce8f86fe2873b1 ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
    (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..


---
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