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Memory safety invariants extracted from a program can help defend and detect against both software and hardware memory violations. For instance, by allowing only specific instructions to access certain memory locations, system can detect out-of-bound or illegal pointer dereferences that lead to correctness and security issues. In this paper, we propose CPU abstractions, called, to specify and check program invariants to provide defense mechanism against both software and hardware memory violations at runtime. ensures that the invariants must be satisfied at every memory accesses. We present a fast invariant address translation and retrieval scheme using a specialized cache. It stores and checks invariants related to global, stack and heap objects. The invariant checks can be performed synchronously or asynchronously. uses synchronous checking for high security-critical programs, while others are protected by asynchronous checking. A fast exception is proposed to alert any violations as soon as possible in order to close the gap for transient attacks. Our evaluation shows that can detect both software and hardware, spatial and temporal memory violations. incurs 53% overhead when checking synchronously, or 15% overhead when checking asynchronously.
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Draco: Architectural and Operating System Support for System Call Security
Abstract—System call checking is extensively used to protect the operating system kernel from user attacks. However, existing solutions such as Seccomp execute lengthy rule-based checking programs against system calls and their arguments, leading to substantial execution overhead. To minimize checking overhead, this paper proposes Draco, a new architecture that caches system call IDs and argument values after they have been checked and validated. System calls are first looked-up in a special cache and, on a hit, skip all checks. We present both a software and a hardware implementation of Draco. The latter introduces a System Call Lookaside Buffer (SLB) to keep recently-validated system calls, and a System Call Target Buffer to preload the SLB in advance. In our evaluation, we find that the average execution time of macro and micro benchmarks with conventional Seccomp checking is 1.14_ and 1.25_ higher, respectively, than on an insecure baseline that performs no security checks. With our software Draco, the average execution time reduces to 1.10_ and 1.18_ higher, respectively, than on the insecure baseline. With our hardware Draco, the execution time is within 1% of the insecure baseline.
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- Award ID(s):
- 2029049
- PAR ID:
- 10293060
- Date Published:
- Journal Name:
- In Proceedings of the 53rd IEEE/ACM International Symposium on Microarchitecture (MICRO-53)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/MICRO50266.2020.00017
