When allocating a record, we round up the allocation size to a multiple
of 8. In this case, any padding bytes should be zeroed, otherwise the
contents of uninitialized memory are written to the ZIL.
This was found using KMSAN.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Closes#12383
bd910fdeb0