Securing your /tmp directory

[vandal]

Securing your /tmp directory could save you from an un-updated PHP script, where someone attempts to write an executable program with malicous code too.

 

I AM NOT RESPONSIBLE FOR ANY PROBLEMS THIS MAY CAUSE


 

that being said, lets get to it:

 

Code:

cd /dev

 

Create 500MB file for our /tmp partition. If you need more space, make count size larger.

 

Code:

dd if=/dev/zero of=tmpMnt bs=1024 count=500000

 

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 -pR /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 -pR /tmp_backup/* /tmp/

 

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