[HADOOP-11202] SequenceFile crashes with client-side encrypted files that are shorter than FileSystem.getStatus(path)

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 2.2.0
• Component/s: fs/s3

Environment

Amazon EMR 3.0.4

• Assignee: Unassigned
• Reporter: Corby Wilson
• Created: 11/Oct/14 19:00
• Updated: 22/Sep/20 11:14
• Resolved: 22/Sep/20 11:14

Description

Encrypted files are often padded to allow for proper encryption on a 2^n-bit boundary. As a result, the encrypted file might be a few bytes bigger than the unencrypted file.

We have a case where an encrypted files is 2 bytes bigger due to padding.

When we run a HIVE job on the file to get a record count (select count from <table>) it runs org.apache.hadoop.mapred.SequenceFileRecordReader and loads the file in through a custom FS InputStream.
The InputStream decrypts the file as it gets read in. Splits are properly handled as it extends both Seekable and Positioned Readable.

When the org.apache.hadoop.io.SequenceFile class intializes it reads in the file size from the FileMetadata which returns the file size of the encrypted file on disk (or in this case in S3).
However, the actual file size is 2 bytes less, so the InputStream will return EOF (-1) before the SequenceFile thinks it's done.
As a result, the SequenceFile$Reader tried to run the next->readRecordLength after the file has been closed and we get a crash.

The SequenceFile class SHOULD, instead, pay attention to the EOF marker from the stream instead of the file size reported in the metadata and set the 'more' flag accordingly.

Sample stack dump from crash

2014-10-10 21:25:27,160 WARN [main] org.apache.hadoop.mapred.YarnChild: Exception running child : java.io.IOException: java.io.IOException: java.io.EOFException
at org.apache.hadoop.hive.io.HiveIOExceptionHandlerChain.handleRecordReaderNextException(HiveIOExceptionHandlerChain.java:121)
at org.apache.hadoop.hive.io.HiveIOExceptionHandlerUtil.handleRecordReaderNextException(HiveIOExceptionHandlerUtil.java:77)
at org.apache.hadoop.hive.shims.HadoopShimsSecure$CombineFileRecordReader.doNextWithExceptionHandler(HadoopShimsSecure.java:304)
at org.apache.hadoop.hive.shims.HadoopShimsSecure$CombineFileRecordReader.next(HadoopShimsSecure.java:220)
at org.apache.hadoop.mapred.MapTask$TrackedRecordReader.moveToNext(MapTask.java:199)
at org.apache.hadoop.mapred.MapTask$TrackedRecordReader.next(MapTask.java:185)
at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:52)
at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:433)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:344)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:162)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1491)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:157)
Caused by: java.io.IOException: java.io.EOFException
at org.apache.hadoop.hive.io.HiveIOExceptionHandlerChain.handleRecordReaderNextException(HiveIOExceptionHandlerChain.java:121)
at org.apache.hadoop.hive.io.HiveIOExceptionHandlerUtil.handleRecordReaderNextException(HiveIOExceptionHandlerUtil.java:77)
at org.apache.hadoop.hive.ql.io.HiveContextAwareRecordReader.doNext(HiveContextAwareRecordReader.java:276)
at org.apache.hadoop.hive.ql.io.CombineHiveRecordReader.doNext(CombineHiveRecordReader.java:101)
at org.apache.hadoop.hive.ql.io.CombineHiveRecordReader.doNext(CombineHiveRecordReader.java:41)
at org.apache.hadoop.hive.ql.io.HiveContextAwareRecordReader.next(HiveContextAwareRecordReader.java:108)
at org.apache.hadoop.hive.shims.HadoopShimsSecure$CombineFileRecordReader.doNextWithExceptionHandler(HadoopShimsSecure.java:302)
... 11 more
Caused by: java.io.EOFException
at java.io.DataInputStream.readInt(DataInputStream.java:392)
at org.apache.hadoop.io.SequenceFile$Reader.readRecordLength(SequenceFile.java:2332)
at org.apache.hadoop.io.SequenceFile$Reader.next(SequenceFile.java:2363)
at org.apache.hadoop.io.SequenceFile$Reader.next(SequenceFile.java:2500)
at org.apache.hadoop.mapred.SequenceFileRecordReader.next(SequenceFileRecordReader.java:82)
at org.apache.hadoop.hive.ql.io.HiveContextAwareRecordReader.doNext(HiveContextAwareRecordReader.java:274)
... 15 more
Sample stack dump:

Issue Links

• is related to: HADOOP-13887 Encrypt S3A data client-side with AWS SDK (S3-CSE)