Invalid rows appear in mysqld-bin.index file, causing server to fail starting. This occurs when WSREP galera replication was enabled. The rows do not point to a valid file but are instead output of wsrep sst.
Example of contents of mysqld-bin.index:
on #maria irc channel was mentioned that:
"looks like when mariadb forks for a sst it should close all fds for the sst"