exporting LD_LIBRARY_PATH problem

sperlis · 12-13-2006, 04:12 AM

Hi all,
I've defined and exported LD_LIBRARY_PATH from .bash_profile. It is built as follows (lets assume it's user1):

Code:

EVN1=${HOME}/version
export ENV1

ENV2=$/home/user2/version
export ENV2

LD_LIBRARY_PATH=${ENV1}/lib:${ENV2}/lib:/usr/local/lib
export LD_LIBRARY_PATH

Everything works well, until I su (no -). After switching to super-user, the environment variables ENV1 and ENV2 are proper:
ENV1 == /home/user1/version
ENV2 == /home/user2/version

However, LD_LIBRARY_PATH is not defined (the bash does not recognize it). I assume the shell treats LD_LIBRARY_PATH in a special way, but I'm not sure how to override it.

Anyone has any ideas?
thanks,

sn68 · 12-13-2006, 05:26 AM

You will have to add & export the LD_LIBRARY_PATH in root .bash_profile also, since .bash_profile is user specific

sperlis · 12-13-2006, 08:23 AM

Please note that I used "su" not "su -". As far as I understand, "su" alone does not invoke the bash scripts. I would like to maintain the environment variables values from user1, while gaining super-user permissions.
ENV1 and ENV2 are retained, while LD_LIBRARY_PATH is lost.

thanks,

sperlis · 12-14-2006, 08:34 AM

LD_LIBRARY_PATH is deleted when changing temporarily to root whether it is exported or not. This is done even when using su without the -. It is done, for example, when running a program with the sticky-bit turned on.
How to go around it:
You can create a temporary variable that is a copy of LD_LIBRARY_PATH in the user. In the root's .bashrc set LD_LIBRARY_PATH to the temporary variable (which is maintained passed the su command).
Just remember that this is certainly a security hole which can be exploited by malicious software and you should really-really want to do it.