A buggy patch
posted to the linux-kernel mailing list in early April was apparently the
last
straw for Greg Kroah-Hartman as it led to the planned reversion of a whole slew of
commits with one thing in common: their origin at the University of
Minnesota (UMN). The patch to the NFSv4 authorization mechanism was duly
questioned by two NFS developers, but it is
not an honest mistake; according to Kroah-Hartman, there has been an attack
of sorts underway as part of some academic research at the university. In
order to be sure that these intentional bugs, many with security
implications, do not continue to haunt Linux, he is working
on reverting commits that came from email addresses with the
umn.edu domain.

Source: LWN.net – [$] Intentionally buggy commits for fame—and papers