Chmod u-x isn't changing anything and I have no idea why

Question

I'm a user on a Debian machine. When I create a file in my home directory, the default permissions appear to be 700, even though umask returns 0022:

eulerz@foo:~$ touch testing
eulerz@foo:~$ ls -l testing 
-rwx------ 1 eulerz users 0 2012-03-15 19:34 testing

In addition, when I create a file in the tmp directory, it doesn't show up as executable, but it does when I move it to my home directory:

eulerz@foo:~$ touch /tmp/made_in_tmp
eulerz@foo:~$ ls -l /tmp/made_in_tmp 
-rw-r--r-- 1 eulerz users 0 2012-03-15 19:39 /tmp/made_in_tmp
eulerz@foo:~$ mv /tmp/made_in_tmp ~
eulerz@foo:~$ ls -l /u/eulerz/made_in_tmp 
-rwxr--r-- 1 eulerz users 0 2012-03-15 19:39 /u/eulerz/made_in_tmp

and, of course, chmod doesn't change this:

eulerz@foo:~$ chmod -v u-x made_in_tmp 
mode of `made_in_tmp' changed to 0644 (rw-r--r--)
eulerz@foo:~$ ls -l /u/eulerz/made_in_tmp 
-rwxr--r-- 1 eulerz users 0 2012-03-15 19:39 /u/eulerz/made_in_tmp

What the heck? Why is this happening? Where is it telling my home directory "set new things as u+x NO MATTER WHAT"?

And this just started happening recently; the older files in my home directory don't have this problem (but I made a copy of one and it did.)

Answer 1

The helpdesk got back to me and explained that it's due to the merging of Windows NTFS permissions with regular POSIX permissions, since the Isilon is configured to be accessible by both NFS and CIFS. So removing the CIFS access would fix the permissions issue.