Shell limits after 12c preinstall rpm

Just a quick note.

Recently I've been using oracle-rdbms-server-12cR1-preinstall package to perform all required pre-reqs for 12c.  This should install required packages, modify kernel parameters and user limits.
Before that I had custom shell limits, like number of open files set to 2048.
After the rpm execution, I've noticed that my user limits have changed

ulimit -n
1024

I expected that and went to limits.conf to change them back,
however when I looked at limits.conf all limits were set as before the package.

cat /etc/security/limits.conf | grep nofile
oracle soft nofile 2048
oracle hard nofile 65536

It appears that the rpm package places the following

/etc/security/limits.d/oracle-rdbms-server-12cR1-preinstall.conf

Which overrides the /etc/security/limits.conf
After changing the oracle-rdbms-server-12cR1-preinstall.conf, everything is back to expected..

ulimit -n
2048

CONCLUSION:
The  oracle-rdbms-server-12cR1-preinstall package places shell limits into /etc/security/limits.d directory.