Recently released Intel processors have been equipped with hardware instruction tracing facilities to securely and efficiently record the program execution path. In this paper, we study a case for data integrity checking based on Intel Processor Trace (Intel PT), the instruction tracing facility on x86 processors. We incorporate software instrumentation and hardware instruction tracing to guarantee fine-grained data integrity without frequently switching the processor mode. We incorporate the idea in a system named DTrace which provides primitives to instruct Intel PT to capture the data load and store events, even current Intel PT implementations only record control transfers. The trace is analyzed before the program makes security-sensitive operations. We apply DTrace in several case studies to show that the primitives that DTrace provides are easy to use and help to enhance data integrity in applications. We further evaluate DTrace with several microbenchmarks to show the time cost that DTrace's data tracing operation incurs. We also evaluate DTrace on Nginx to show the performance impact when Nginx is enhanced in security to provide the integrity during the runtime execution for programmer-defined security sensitive data. We find the performance overhead that DTrace incurs for the data tracing is moderate.

acquired reactive perforating collagenosis (arPC) is a rare chronic skin disease associated with various internal diseases, particularly diabetes and chronic renal failure. the present study describes the case of a patient with arPC combined with methicillin-resistant Staphylococcus aureus (MrSa), in an aim to broaden the current understanding of arPC. a 75-year-old female presented with a 5-year history of pruritus and ulcerative eruptions on the trunk of her body, which became more severe within 1 year. a cutaneous examination revealed a diffuse distribution of erythema and papules, and nodules of various sizes, some of which sagged at the center and had a dark brown crust. a histopathological analysis revealed typical perforations of the collagen fibers. The patient was initially treated with topical corticosteroids and oral antihistamines for skin lesions and pruritus. Medications for glucose control were also administered. Upon the second admission, a combination of antibiotics and acitretin was added. the keratin plug shrank, and the pruritus was relieved. To date, to the best of our knowledge, this is the first reported case of concurrent arPC and MrSa.

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