Recently ran into a problem where user "oracle" was unable to start or stop listeners:

oracle$ srvctl stop listener
PRCR-1065 : Failed to stop resource ora.LISTENER.lsnr
CRS-0245:  User doesn't have enough privilege to perform the operation
CRS-0245:  User doesn't have enough privilege to perform the operation
PRCR-1065 : Failed to stop resource ora.LISTENER_IB.lsnr
CRS-0245:  User doesn't have enough privilege to perform the operation
CRS-0245:  User doesn't have enough privilege to perform the operation

The system is currently "fixed":

oracle$ srvctl start listener

oracle$ srvctl status listener
Listener LISTENER is enabled
Listener LISTENER is running on node(s): etc9cn02,etc9cn01
Listener LISTENER_IB is enabled
Listener LISTENER_IB is running on node(s): etc9cn02,etc9cn01

oracle$ srvctl stop listener

oracle$ srvctl status listener
Listener LISTENER is enabled
Listener LISTENER is not running
Listener LISTENER_IB is enabled
Listener LISTENER_IB is not running

oracle$ srvctl start listener

How it was "fixed":

Before:

# crsctl status resource ora.LISTENER.lsnr -p | grep ACL=
ACL=owner:root:rwx,pgrp:root:r-x,other::r--

# crsctl status resource ora.LISTENER_IB.lsnr -p | grep ACL=
ACL=owner:root:rwx,pgrp:root:r-x,other::r--

"Fix":

# crsctl setperm resource ora.LISTENER.lsnr -o oracle
# crsctl setperm resource ora.LISTENER.lsnr -g oinstall
# crsctl setperm resource ora.LISTENER_IB.lsnr -g oinstall
# crsctl setperm resource ora.LISTENER_IB.lsnr -o oracle

After:

# crsctl status resource ora.LISTENER.lsnr -p | grep ACL=
ACL=owner:oracle:rwx,pgrp:oinstall:r-x,other::r--

# crsctl status resource ora.LISTENER_IB.lsnr -p | grep ACL=
ACL=owner:oracle:rwx,pgrp:oinstall:r-x,other::r--

I may never know how the system got into this state.