According to the C standard, it is invalid to copy beyond the end of an
object, even if that object is obviously a member of a larger object (a
struct, in this case).
Appease the standard and Coverity by refactoring the copy in a
straightforward way. No functional change.
Reported by: Coverity (CWE-120)
CIDs: 1007819, 1007820, 1007821, 1007822, 1009668, 1009669
Security: no (false positive detection)
Sponsored by: Dell EMC Isilon
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