As far as I can tell many kernel versions contained the source code bug.
(I'd like some more information on exactly what the problem was if
anyone cares to share..the proposed patch didn't give much in the way of
specifics.)
However, in order to trigger the problem you also need to have NTP
servers that were erroneously broadcasting the addition of a leap second.
So most people didn't see the issue because there wasn't supposed to be
a leap second added this year...but they would have seen it the next
time a leap second was added.
Chris
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