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

ld.so and LD_PRELOAD

The above URL contains a link to a discussion about LD_PRELOAD in SE Linux.

It seems that if you can get root access to a SE Linux machine then LD_PRELOAD 
can be used (it's allowed if your real and effective UIDs match) to exploit 
system programs.

The solution to this is to have ld-linux.so do a check for whether the secsid 
and osecsid of the process are equal in addition to the check for effective 
and real UIDs.

Now I don't want to maintain a SE Linux version of libc6 for a special 
/lib/ld-linux.so.2 if I can avoid it.  Also I think it would be ideal if the 
functionality in this regard could support multiple security systems.  Would 
it be practical for /lib/ld-linux.so.2 to load a shared object to determine 
whether LD_PRELOAD is allowed?

http://www.coker.com.au/selinux/   My NSA Security Enhanced Linux packages
http://www.coker.com.au/bonnie++/  Bonnie++ hard drive benchmark
http://www.coker.com.au/postal/    Postal SMTP/POP benchmark
http://www.coker.com.au/~russell/  My home page

Reply to: