MySQL Bugs: #76883: Checksum calculation of rows not including header bits

Bug #76883	Checksum calculation of rows not including header bits
Submitted:	29 Apr 2015 11:26	Modified:	14 Jan 2016 22:37
Reporter:	Mikael Ronström	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Cluster: Cluster (NDB) storage engine	Severity:	S3 (Non-critical)
Version:	7.4.7	OS:	Any
Assigned to:		CPU Architecture:	Any

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Description:
One important feature of MySQL Cluster is the ability to allow for the fixed part of rows to be checksummed to ensure that users never get to see corrupted data.

This feature does however not checksum the header bits of the tuple header.

There is code that still recalculates the checksum even when only toggling bits in the tuple header.

How to repeat:
Found when optimising checksum calculation as part of fix for BUG#20904721

Suggested fix:
Include header bits also in checksum calculation and ensure optimisation of only working with header bits is working.

Fixed in NDB 7.2.21/7.3.10/7.4.7. See BUG#76741 for documentation info.

Closed.