When an ODA has been patched from one release to another, it is easy to get the filesystem getting maxed out, preventing subsequent upgrade to take place.
To free some space, are are some hints:
#1 Remove old grid ORACLE_HOMEs
A backup on another system is also suggested. And if not possible, a quick win may be to remove the logfiles under
/u01/app/<old grid home>/rdbms/log /u01/app/<old grid home>/log
#2 Use oakcli cleanrepo
This utility can be used to remove old patches
See How to Clean Up Old Staged Patches on ODA Using OAK Commands 1681062.1
#3 Use purseLogs
This utility can be used to remove old logfiles
See purgeLogs: Cleanup traces, logs in one command 2081655.1