DieHard: Probabilistic Memory Safety for Unsafe Languages
Speaker: Emery Berger , Assistant Professor, University of Massachusetts, Amherst
Date: March 24 2006
Time: 2:00PM to 3:00PM
Location: D463 Star Conference Room
Host: Martin Rinard, CSAIL
Contact: Mary McDavitt, 617-253-9620, mmcdavit@csail.mit.edu
Abstract:
Applications written in unsafe languages like C and C++ are vulnerable
to memory errors such as buffer overflows, dangling pointers, and reads
of uninitialized data. Such errors can lead to program crashes, security
vulnerabilities, and unpredictable behavior. We present DieHard, a
runtime system that tolerates these errors while probabilistically
maintaining soundness. DieHard uses randomization and replication to
achieve probabilistic memory safety by approximating an infinite-sized
heap. DieHard's memory manager randomizes the location of objects in a
heap that is at least twice as large as required. This algorithm
prevents heap corruption and provides a probabilistic guarantee of
avoiding memory errors. For additional safety, DieHard can operate in a
replicated mode where multiple replicas of the same application are run
simultaneously. By initializing each replica with a different random
seed and requiring agreement on output, the replicated version of
DieHard increases the likelihood of correct execution because errors are
unlikely to have the same effect across all replicas. We present
analytical and experimental results that show DieHard's resilience to a
wide range of memory errors, including a heap-based buffer overflow in
an actual application.
Joint work with Ben Zorn of Microsoft Research.
Bio:
Emery Berger is an Assistant Professor at the University of
Massachusetts Amherst. He received his Ph.D. at the University of Texas
at Austin in 2002. Berger's research focuses on improving the
performance and reliability of modern computer systems. His work spans
programming languages, runtime systems, and operating systems, with a
particular focus on memory management. Berger is the creator of Hoard, a
widely-used scalable memory manager, and is part of a research group
singled out by NSF site visitors as the best memory management group in
the country. He leads the PLASMA lab at UMass and is a 2004 NSF CAREER
Award recipient.
See other events that are part of
See other events happening in March 2006
