NPE in SSTableReader.invalidateCacheKey

ERROR [NonPeriodicTasks:1] 2015-09-03 05:24:51,056 CassandraDaemon.java:223 - Exception in thread Thread[NonPeriodicTasks:1,5,main]
java.lang.NullPointerException: null
        at org.apache.cassandra.io.sstable.SSTableReader.invalidateCacheKey(SSTableReader.java:1445) ~[apache-cassandra-2.1.7.jar:2.1.7]
        at org.apache.cassandra.io.sstable.SSTableRewriter$1.run(SSTableRewriter.java:323) ~[apache-cassandra-2.1.7.jar:2.1.7]
        at org.apache.cassandra.io.sstable.SSTableReader$5.run(SSTableReader.java:1024) ~[apache-cassandra-2.1.7.jar:2.1.7]
        at org.apache.cassandra.io.sstable.SSTableReader$InstanceTidier$1.run(SSTableReader.java:2146) ~[apache-cassandra-2.1.7.jar:2.1.7]
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[na:1.8.0_51]
        at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[na:1.8.0_51]
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) ~[na:1.8.0_51]
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) ~[na:1.8.0_51]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) ~[na:1.8.0_51]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_51]
        at java.lang.Thread.run(Thread.java:745) [na:1.8.0_51]