[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Update of tomcat6 - JVM_TMP issue + Dealing with Debian-Ubuntu delta



Thierry Carrez wrote:
> Niels Thykier wrote:
>> Thierry Carrez wrote:
>>> I still think /tmp is the right location for JVM temp files, since they
>>> aren't cache files and should be cleaned up at system restart. If you
>>> don't want them to be in /tmp, you will have to use a specific directory
>>> (separate from /var/cache/tomcat6) and make sure it's cleaned up
>>> periodically. You mention a security problem as the main reason to
>>> change that, could you elaborate ? This code looks secure to me.
>> I based on a certain lintian tag[1] and the "symlink race"[2] - I admit
>>  I am not sure to what extend someone could use the attack; the attack
>> window is very short as I understand it and does require local user
>> access[3].
> 
> The code doesn't use temporary files but a temporary directory. mkdir
> being atomic, if /tmp/tomcat-temp can't be created because it already
> exists, the code fails. There is no attack window, that's quite secure.
> 

Dang, you are right. As long as we do not use "-p" we should be okay [1]
- thanks for the clarification.

>> On a related note; shouldn't the postrm script be removing the JVM_TMP
>> dir rather than leaving it till next reboot?
> 
> It could do that specifically on purge, but I don't think it /needs/ to.
> 

If we do it using /tmp/tomcat-temp we are likely to trigger the
previously mention lintian warning if we clean it in the postrm. I moved
jetty's tmp dir to avoid that tag.



I will revert to /tmp/tomcat-temp and leave /tmp/tomcat-temp be on
purge, unless anyone else following this debate voices objections.

~Niels

[1] 'atomic'ness aside, mkdir -p does not fail if the link points to an
existing dir. In that case the script would change the owner of a given
dir to tomcat6.


Attachment: signature.asc
Description: OpenPGP digital signature


Reply to: