cannot read symbolic link : Invalid argument

When I run a container by docker for a long time, I met an unexpected bug about symbolic link.

In the container, a symbolic link has been broken. The mounted filesystem is
overlay2. The broken symbolic link is libipfwinner.so ´╝îit point to libipfwinner.so.0.0.0.5.

I think it might be a bug of overlayfs or docker. I cannot reproduce this
problem. It only happened once after a long running time.

Expected behavior

sh-4.2$ ls  /lib/ -ll | grep libipfw
lrwxrwxrwx 1 root root       23 Feb 21 09:31 libipfwinner.so ->libipfwinner.so.0.0.0.5
-rwxr-xr-x 1 root root    69808 Feb 21 09:31 libipfwinner.so.0.0.0.5

Actual behavior

sh-4.2$ ls /lib/ -ll | grep libipfwinner
ls: cannot read symbolic link /lib/libipfwinner.so: Invalid argument
lrwxrwxrwx 1 root root       23 Feb 22 09:42 libipfwinner.so
-rwxr-xr-x 1 root root    69808 Feb 22 09:42 libipfwinner.so.0.0.0.5

sh-4.2$ cat libipfwinner.so
cat: libipfwinner.so: Too many levels of symbolic links    

Device Info:

sh-4.2$ uname -a
Linux xx 4.9.29 #1 SMP PREEMPT Fri Dec 21 16:00:00 CST 2018 x86_64 x86_64 x86_64 GNU/Linux

sh-4.2$ df
Filesystem     1K-blocks    Used Available Use% Mounted on
overlay          7891460 2300196   5591264  30% /

Docker info

Containers: 1  
Running: 1  
Paused: 0  
Stopped: 0  
Images: 1  
Server Version: 18.06.0-ce  
Storage Driver: overlay2  
Backing Filesystem: tmpfs  
Supports d_type: true  
Native Overlay Diff: true  
Logging Driver: json-file  
Cgroup Driver: cgroupfs  

Source: StackOverflow