BUG: unable to handle kernel NULL pointer dereference at 00000000000000d0
PGD 800000013d62a067 P4D 800000013d62a067 PUD 13d62d067 PMD 0 
Oops: 0000 [#1] SMP PTI
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 16117 Comm: syz-executor3 Not tainted 4.17.0+ #18
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:slab_equal_or_root mm/slab.h:228 [inline]
RIP: 0010:cache_from_obj mm/slab.h:374 [inline]
RIP: 0010:kmem_cache_free+0x31d/0x2bc0 mm/slub.c:3022
RSP: 0018:ffff88011161f458 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000000000d0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffea0006000030
RBP: ffff88011161f5a8 R08: 0000000000000000 R09: 0000000000000002
R10: 0000000000000000 R11: ffffffff81cc5340 R12: 0000000000000000
R13: ffff8801d236ef00 R14: 0000000000000000 R15: ffffea0000000000
FS:  00007fa867c16700(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000d0 CR3: 000000013d672000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ep_unregister_pollwait fs/eventpoll.c:615 [inline]
 ep_remove+0x323/0xab0 fs/eventpoll.c:778
 eventpoll_release_file+0x140/0x220 fs/eventpoll.c:1003
 eventpoll_release include/linux/eventpoll.h:66 [inline]
 __fput+0x63a/0xa30 fs/file_table.c:200
 ____fput+0x37/0x40 fs/file_table.c:243
 task_work_run+0x22e/0x2b0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x110e/0x3930 kernel/exit.c:867
 do_group_exit+0x1a0/0x360 kernel/exit.c:970
 get_signal+0x1405/0x1ec0 kernel/signal.c:2482
 do_signal+0xb8/0x1d20 arch/x86/kernel/signal.c:810
 exit_to_usermode_loop arch/x86/entry/common.c:162 [inline]
 prepare_exit_to_usermode+0x271/0x3a0 arch/x86/entry/common.c:196
 syscall_return_slowpath+0xe9/0x710 arch/x86/entry/common.c:265
 do_syscall_64+0x1ad/0x230 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x455ab9
RSP: 002b:00007fa867c15ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000000 RBX: 000000000072bec0 RCX: 0000000000455ab9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000072bec0
RBP: 000000000072bec0 R08: 0000000000000000 R09: 000000000072bea0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000a3e81f R14: 00007fa867c169c0 R15: 0000000000000000
Code: 31 e9 48 f7 d0 48 21 c8 0f 84 67 01 00 00 4d 39 ec 0f 84 7b 01 00 00 89 55 a0 49 8d 9c 24 d0 00 00 00 4d 85 f6 0f 85 6f 11 00 00 <4c> 8b 2b 48 89 df e8 68 91 03 00 48 8b 00 48 0b 45 b8 74 16 4c 
RIP: slab_equal_or_root mm/slab.h:228 [inline] RSP: ffff88011161f458
RIP: cache_from_obj mm/slab.h:374 [inline] RSP: ffff88011161f458
RIP: kmem_cache_free+0x31d/0x2bc0 mm/slub.c:3022 RSP: ffff88011161f458
CR2: 00000000000000d0
---[ end trace 037b4318a761f445 ]---