tmp folder

[mmscwebmaster]

There is a folder called tmp at the root level on the cPanel website which I am now managing. Can all these historic files be deleted without upsetting anything?

[1a-Websolutions]

Hi,

don't delete mysql.sock - all other Data can you delete.

If you delte mysql.sock you need to restart the Mysql - if it don't work - restart the Server.

Regards

[shivinvijai]

Hi,

It would be worthwhile to give /tmp it's own partition and mount it using noexec- This would protect your system from MANY local and remote exploits of rootkits being run from your /tmp folder.

What we are doing it creating a file that we will use to mount at /tmp. So log into SSH and SU to root so we may being!

cd /dev

dd if=/dev/zero of=tmpMnt bs=1024 count=100000

Make an extended filesystem for our tmpMnt file

/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.

cd /

cp -R /tmp /tmp_backup

Mount the new /tmp filesystem with noexec

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

chmod 1777 /tmp

Copy everything back to new /tmp and remove backup

cp -R /tmp_backup/* /tmp/

rm -rf /tmp_backup

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

vi /etc/fstab

You should see something like this:

/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
/dev/tmpMnt /tmp ext2 loop,noexec,nosuid,rw 0 0

(Each space is a tab)
Save it!

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:

bash: ./a.out: Permission denied

Thanks

[ramprage]

shivinvijai - it would be nice if you mentioned you didn't write this and you copied and pasted the article from my site http://www.webhostgear.com/34.html

[cpanelkenneth]

/scripts/securetmp also creates a loopback file to mount noexec on /tmp

It does that if /tmp is not already a partition (slice for FreeBSD)

It usually runs in /etc/rc.local

[Infopro]

shivinvijai - it would be nice if you mentioned you didn't write this and you copied and pasted the article from my site http://www.webhostgear.com/34.html

Lots of great stuff there too.



typo check

So log into SSH and SU to root so we may being!