I See Devil In My Linux 7.1

[Li Bing]

Hi, all,   It is really strange that I can create a directory with mkdir. But I can't see it. And only the directory named, "xml_doc", can be seen. But it really exists. I can go into it and list all the files under it. Other directories are normal.   This morning I could not use the command, "ls", because of permission problems. I have to add "x" to /bin/ls. Maybe my RedHat 7.1 is hacked?   Thanks, Li Bing