Make an extended filesystem for our tmpMnt file

code:
/sbin/mke2fs /dev/tmpMnt

Backup your /tmp dir- I had mysql.sock file that I needed to recreate the symbolic link for. Other programs may use it to store cache files or whatever.

code:
cd /

code:
cp -R /tmp /tmp_backup

Mount the new /tmp filesystem with noexec

code:
mount -o loop,noexec,nosuid,rw /dev/tmpMnt /tmp

code:
chmod 0777 /tmp

Copy everything back to new /tmp and remove backup

code:
cp -R /tmp_backup/* /tmp/

code:
rm -rf /tmp_backup

Now we need to add this to fstab so it mounts automatically on reboots.

code:
pico -w /etc/fstab

You should see something like this:
code:
/dev/hda3               /                       ext3    defaults,usrquota        1 1
/dev/hda1               /boot                   ext3    defaults        1 2
none                    /dev/pts                devpts  gid=5,mode=620  0 0
none                    /proc                   proc    defaults        0 0
none                    /dev/shm                tmpfs   defaults        0 0
/dev/hda2               swap                    swap    defaults        0 0

At the bottom add
code:
/dev/tmpMnt             /tmp                    ext2    loop,noexec,nosuid,rw  0 0

(Each space is a tab)
Save it!
Ctrl + X and Y

Your done- /tmp is now mounted as noexec. You can sleep a little bit safer tonight. I created a hello world c++ and compiled it then moved it to /tmp. Upon trying to run it (even chmod +x'ed), it gives the following error:

code:
bash: ./a.out: Permission denied