syzbot

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:
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Modules linked in:
CPU: 0 PID: 1549 Comm: kworker/0:2 Not tainted 4.15.0-rc8+ #264
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events bpf_map_free_deferred
RIP: 0010:css_put include/linux/cgroup.h:386 [inline]
RIP: 0010:cgroup_put include/linux/cgroup.h:415 [inline]
RIP: 0010:cgroup_fd_array_put_ptr+0x71/0x2a0 kernel/bpf/arraymap.c:573
RSP: 0018:ffff8801d35af490 EFLAGS: 00010a02
RAX: 10f40039400001e5 RBX: 1ffff1003a6b5e92 RCX: ffffffff8180f5a5
RDX: 0000000000000000 RSI: ffff8801d8b55464 RDI: 87a001ca00000f2b
RBP: ffff8801d35af518 R08: 1ffff1003a6b5e70 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 87a001ca00000ebf
R13: ffff8801d35af4f0 R14: dffffc0000000000 R15: 87a001ca00000ebf
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000203e2fe4 CR3: 0000000006822003 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fd_array_map_delete_elem kernel/bpf/arraymap.c:420 [inline]
 bpf_fd_array_map_clear kernel/bpf/arraymap.c:461 [inline]
 cgroup_fd_array_free+0xd2/0x150 kernel/bpf/arraymap.c:578
 bpf_map_free_deferred+0xb0/0xe0 kernel/bpf/syscall.c:217
 process_one_work+0xbbf/0x1b10 kernel/workqueue.c:2112
 worker_thread+0x223/0x1990 kernel/workqueue.c:2246
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x37/0x50 arch/x86/entry/entry_64.S:530
Code: 45 88 40 f5 80 81 c7 00 f1 f1 f1 f1 c7 40 04 00 f2 f2 f2 c7 40 08 f3 f3 f3 f3 e8 1b 22 ef ff 49 8d 7c 24 6c 48 89 f8 48 c1 e8 03 <42> 0f b6 14 30 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 
RIP: css_put include/linux/cgroup.h:386 [inline] RSP: ffff8801d35af490
RIP: cgroup_put include/linux/cgroup.h:415 [inline] RSP: ffff8801d35af490
RIP: cgroup_fd_array_put_ptr+0x71/0x2a0 kernel/bpf/arraymap.c:573 RSP: ffff8801d35af490
---[ end trace b83cbbb5164d5c72 ]---
Kernel panic - not syncing: Fatal exception
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Kernel Offset: disabled
Rebooting in 86400 seconds..