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SUMMARY:Systematic Testing for Dynamically Updatable Software - Michael Hi
 cks (University of Maryland)
DTSTART:20090507T150000Z
DTEND:20090507T160000Z
UID:TALK17671@talks.cam.ac.uk
CONTACT:Eiko Yoneki
DESCRIPTION:Recent years have seen significant advances in dynamic softwar
 e updating (DSU) systems\, which allow programs to be patched on the fly. 
 However\, a significant challenge remains: How can we ensure the act of ap
 plying a patch does not itself introduce errors? In this paper\, we addres
 s this problem by presenting a new systematic testing methodology for upda
 table programs. Our idea is to transform standard system tests into update
  tests that execute as before\, but each transformed test applies a patch 
 at a different update point during execution. To mitigate the increase in 
 the number of tests\, we developed an algorithm for test suite minimizatio
 n that finds a subset of update points that\, if fully tested\, yields the
  equivalent to full update point coverage. We implemented our approach and
  evaluated it on OpenSSH and vsftpd\, two widely used server applications.
  We found that minimization is highly effective\; that when updates are al
 lowed almost anywhere\, many update tests fail\; and that excluding type u
 nsafe update points eliminates nearly\, but not quite all\, failing update
  tests.
LOCATION:FW26\, Computer Laboratory\, William Gates Builiding
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