Improving File System Performance of Mobile Storage Systems Using A
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FIT to WORK: IMPROVING the SECURITY of MONITORED EMPLOYEES' HEALTH DATA Elizabeth A. Brown INTRODUCTION Imagine Coming to Work
FIT TO WORK: IMPROVING THE SECURITY OF MONITORED EMPLOYEES' HEALTH DATA Elizabeth A. Brown1 INTRODUCTION Imagine coming to work one day and finding that your employer has given everyone in the company a wearable FitBit health monitor, free of charge. You pop the FitBit on, grateful for another bit of help in managing the health concerns that nag at you persistently but which never quite rise to the top of your priority list. At your next performance review, your supervisor expresses concern about your anxiety levels. Although your work output is slightly off, she notes, there has been a correlation in your lack of sleep and exercise, and she suspects you are depressed. You wonder how your employer might know these things, whether or not they are true, and then you remember the FitBit. Your supervisor then tells you that the promotion you had wanted is going to a colleague who is “better equipped to handle the demands of the job.” You interview for another job, and are asked to provide the password to the HealthDrive account that centralizes the fitness data all the apps on your iPhone collect about you during the day. Similar scenarios are playing out now in workplaces across the country, and will do so more frequently as the personal health sensor market and employee monitoring trends continue to grow. Employers are making key decisions based on employees’ biometric data, collected from specialized devices like a FitBit or the health-related apps installed on mobile phones. BP, for example, adjusts its employees’ health care premiums depending on how much physical activity their wearable FitBit devices monitor – devices that BP provides to thousands of employees, their spouses, and retirees for free. -
Your Voice Assistant Is Mine: How to Abuse Speakers to Steal Information and Control Your Phone ∗ †
Your Voice Assistant is Mine: How to Abuse Speakers to Steal Information and Control Your Phone ∗ y Wenrui Diao, Xiangyu Liu, Zhe Zhou, and Kehuan Zhang Department of Information Engineering The Chinese University of Hong Kong {dw013, lx012, zz113, khzhang}@ie.cuhk.edu.hk ABSTRACT General Terms Previous research about sensor based attacks on Android platform Security focused mainly on accessing or controlling over sensitive compo- nents, such as camera, microphone and GPS. These approaches Keywords obtain data from sensors directly and need corresponding sensor invoking permissions. Android Security; Speaker; Voice Assistant; Permission Bypass- This paper presents a novel approach (GVS-Attack) to launch ing; Zero Permission Attack permission bypassing attacks from a zero-permission Android application (VoicEmployer) through the phone speaker. The idea of 1. INTRODUCTION GVS-Attack is to utilize an Android system built-in voice assistant In recent years, smartphones are becoming more and more popu- module – Google Voice Search. With Android Intent mechanism, lar, among which Android OS pushed past 80% market share [32]. VoicEmployer can bring Google Voice Search to foreground, and One attraction of smartphones is that users can install applications then plays prepared audio files (like “call number 1234 5678”) in (apps for short) as their wishes conveniently. But this convenience the background. Google Voice Search can recognize this voice also brings serious problems of malicious application, which have command and perform corresponding operations. With ingenious been noticed by both academic and industry fields. According to design, our GVS-Attack can forge SMS/Email, access privacy Kaspersky’s annual security report [34], Android platform attracted information, transmit sensitive data and achieve remote control a whopping 98.05% of known malware in 2013. -
Fragmentation in Large Object Repositories
Fragmentation in Large Object Repositories Experience Paper Russell Sears Catharine van Ingen University of California, Berkeley Microsoft Research [email protected] [email protected] ABSTRACT 1. INTRODUCTION Fragmentation leads to unpredictable and degraded application Application data objects continue to increase in size. performance. While these problems have been studied in detail Furthermore, the increasing popularity of web services and other for desktop filesystem workloads, this study examines newer network applications means that systems that once managed static systems such as scalable object stores and multimedia archives of “finished” objects now manage frequently modified repositories. Such systems use a get/put interface to store objects. versions of application data. Rather than updating these objects in In principle, databases and filesystems can support such place, typical archives either store multiple versions of the objects applications efficiently, allowing system designers to focus on (the V of WebDAV stands for “versioning” [25]), or simply do complexity, deployment cost and manageability. wholesale replacement (as in SharePoint Team Services [19]). Similarly, applications such as personal video recorders and Although theoretical work proves that certain storage policies media subscription servers continuously allocate and delete large, behave optimally for some workloads, these policies often behave transient objects. poorly in practice. Most storage benchmarks focus on short-term behavior or do not measure fragmentation. We compare SQL Applications store large objects as some combination of files in Server to NTFS and find that fragmentation dominates the filesystem and as BLOBs (binary large objects) in a database. performance when object sizes exceed 256KB-1MB. NTFS Only folklore is available regarding the tradeoffs. -
ECE 598 – Advanced Operating Systems Lecture 19
ECE 598 { Advanced Operating Systems Lecture 19 Vince Weaver http://web.eece.maine.edu/~vweaver [email protected] 7 April 2016 Announcements • Homework #7 was due • Homework #8 will be posted 1 Why use FAT over ext2? • FAT simpler, easy to code • FAT supported on all major OSes • ext2 faster, more robust filename and permissions 2 btrfs • B-tree fs (similar to a binary tree, but with pages full of leaves) • overwrite filesystem (overwite on modify) vs CoW • Copy on write. When write to a file, old data not overwritten. Since old data not over-written, crash recovery better Eventually old data garbage collected • Data in extents 3 • Copy-on-write • Forest of trees: { sub-volumes { extent-allocation { checksum tree { chunk device { reloc • On-line defragmentation • On-line volume growth 4 • Built-in RAID • Transparent compression • Snapshots • Checksums on data and meta-data • De-duplication • Cloning { can make an exact snapshot of file, copy-on- write different than link, different inodles but same blocks 5 Embedded • Designed to be small, simple, read-only? • romfs { 32 byte header (magic, size, checksum,name) { Repeating files (pointer to next [0 if none]), info, size, checksum, file name, file data • cramfs 6 ZFS Advanced OS from Sun/Oracle. Similar in idea to btrfs indirect still, not extent based? 7 ReFS Resilient FS, Microsoft's answer to brtfs and zfs 8 Networked File Systems • Allow a centralized file server to export a filesystem to multiple clients. • Provide file level access, not just raw blocks (NBD) • Clustered filesystems also exist, where multiple servers work in conjunction. -
Ext4 File System and Crash Consistency
1 Ext4 file system and crash consistency Changwoo Min 2 Summary of last lectures • Tools: building, exploring, and debugging Linux kernel • Core kernel infrastructure • Process management & scheduling • Interrupt & interrupt handler • Kernel synchronization • Memory management • Virtual file system • Page cache and page fault 3 Today: ext4 file system and crash consistency • File system in Linux kernel • Design considerations of a file system • History of file system • On-disk structure of Ext4 • File operations • Crash consistency 4 File system in Linux kernel User space application (ex: cp) User-space Syscalls: open, read, write, etc. Kernel-space VFS: Virtual File System Filesystems ext4 FAT32 JFFS2 Block layer Hardware Embedded Hard disk USB drive flash 5 What is a file system fundamentally? int main(int argc, char *argv[]) { int fd; char buffer[4096]; struct stat_buf; DIR *dir; struct dirent *entry; /* 1. Path name -> inode mapping */ fd = open("/home/lkp/hello.c" , O_RDONLY); /* 2. File offset -> disk block address mapping */ pread(fd, buffer, sizeof(buffer), 0); /* 3. File meta data operation */ fstat(fd, &stat_buf); printf("file size = %d\n", stat_buf.st_size); /* 4. Directory operation */ dir = opendir("/home"); entry = readdir(dir); printf("dir = %s\n", entry->d_name); return 0; } 6 Why do we care EXT4 file system? • Most widely-deployed file system • Default file system of major Linux distributions • File system used in Google data center • Default file system of Android kernel • Follows the traditional file system design 7 History of file system design 8 UFS (Unix File System) • The original UNIX file system • Design by Dennis Ritche and Ken Thompson (1974) • The first Linux file system (ext) and Minix FS has a similar layout 9 UFS (Unix File System) • Performance problem of UFS (and the first Linux file system) • Especially, long seek time between an inode and data block 10 FFS (Fast File System) • The file system of BSD UNIX • Designed by Marshall Kirk McKusick, et al. -
Understanding and Mitigating Security Risks of Voice-Controlled Third-Party Functions on Virtual Personal Assistant Systems
Dangerous Skills: Understanding and Mitigating Security Risks of Voice-Controlled Third-Party Functions on Virtual Personal Assistant Systems Nan Zhang∗, Xianghang Mi∗, Xuan Fengy∗, XiaoFeng Wang∗, Yuan Tianz and Feng Qian∗ ∗Indiana University, Bloomington Email: fnz3, xmi, xw7, [email protected] yBeijing Key Laboratory of IOT Information Security Technology, Institute of Information Engineering, CAS, China Email: [email protected] zUniversity of Virginia Email: [email protected] Abstract—Virtual personal assistants (VPA) (e.g., Amazon skills by Amazon and actions by Google1) to offer further Alexa and Google Assistant) today mostly rely on the voice helps to the end users, for example, order food, manage bank channel to communicate with their users, which however is accounts and text friends. In the past year, these ecosystems known to be vulnerable, lacking proper authentication (from the user to the VPA). A new authentication challenge, from the VPA are expanding at a breathtaking pace: Amazon claims that service to the user, has emerged with the rapid growth of the VPA already 25,000 skills have been uploaded to its skill market to ecosystem, which allows a third party to publish a function (called support its VPA (including the Alexa service running through skill) for the service and therefore can be exploited to spread Amazon Echo) [1] and Google also has more than one thousand malicious skills to a large audience during their interactions actions available on its market for its Google Home system with smart speakers like Amazon Echo and Google Home. In this paper, we report a study that concludes such remote, large- (powered by Google Assistant). -
Filesystem Considerations for Embedded Devices ELC2015 03/25/15
Filesystem considerations for embedded devices ELC2015 03/25/15 Tristan Lelong Senior embedded software engineer Filesystem considerations ABSTRACT The goal of this presentation is to answer a question asked by several customers: which filesystem should you use within your embedded design’s eMMC/SDCard? These storage devices use a standard block interface, compatible with traditional filesystems, but constraints are not those of desktop PC environments. EXT2/3/4, BTRFS, F2FS are the first of many solutions which come to mind, but how do they all compare? Typical queries include performance, longevity, tools availability, support, and power loss robustness. This presentation will not dive into implementation details but will instead summarize provided answers with the help of various figures and meaningful test results. 2 TABLE OF CONTENTS 1. Introduction 2. Block devices 3. Available filesystems 4. Performances 5. Tools 6. Reliability 7. Conclusion Filesystem considerations ABOUT THE AUTHOR • Tristan Lelong • Embedded software engineer @ Adeneo Embedded • French, living in the Pacific northwest • Embedded software, free software, and Linux kernel enthusiast. 4 Introduction Filesystem considerations Introduction INTRODUCTION More and more embedded designs rely on smart memory chips rather than bare NAND or NOR. This presentation will start by describing: • Some context to help understand the differences between NAND and MMC • Some typical requirements found in embedded devices designs • Potential filesystems to use on MMC devices 6 Filesystem considerations Introduction INTRODUCTION Focus will then move to block filesystems. How they are supported, what feature do they advertise. To help understand how they compare, we will present some benchmarks and comparisons regarding: • Tools • Reliability • Performances 7 Block devices Filesystem considerations Block devices MMC, EMMC, SD CARD Vocabulary: • MMC: MultiMediaCard is a memory card unveiled in 1997 by SanDisk and Siemens based on NAND flash memory. -
Implementing Nfsv4 in the Enterprise: Planning and Migration Strategies
Front cover Implementing NFSv4 in the Enterprise: Planning and Migration Strategies Planning and implementation examples for AFS and DFS migrations NFSv3 to NFSv4 migration examples NFSv4 updates in AIX 5L Version 5.3 with 5300-03 Recommended Maintenance Package Gene Curylo Richard Joltes Trishali Nayar Bob Oesterlin Aniket Patel ibm.com/redbooks International Technical Support Organization Implementing NFSv4 in the Enterprise: Planning and Migration Strategies December 2005 SG24-6657-00 Note: Before using this information and the product it supports, read the information in “Notices” on page xi. First Edition (December 2005) This edition applies to Version 5, Release 3, of IBM AIX 5L (product number 5765-G03). © Copyright International Business Machines Corporation 2005. All rights reserved. Note to U.S. Government Users Restricted Rights -- Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents Notices . xi Trademarks . xii Preface . xiii The team that wrote this redbook. xiv Acknowledgments . xv Become a published author . xvi Comments welcome. xvii Part 1. Introduction . 1 Chapter 1. Introduction. 3 1.1 Overview of enterprise file systems. 4 1.2 The migration landscape today . 5 1.3 Strategic and business context . 6 1.4 Why NFSv4? . 7 1.5 The rest of this book . 8 Chapter 2. Shared file system concepts and history. 11 2.1 Characteristics of enterprise file systems . 12 2.1.1 Replication . 12 2.1.2 Migration . 12 2.1.3 Federated namespace . 13 2.1.4 Caching . 13 2.2 Enterprise file system technologies. 13 2.2.1 Sun Network File System (NFS) . 13 2.2.2 Andrew File System (AFS) . -
External Flash Filesystem for Sensor Nodes with Sparse Resources
External Flash Filesystem for Sensor Nodes with sparse Resources Stephan Lehmann Stephan Rein Clemens Gühmann stephan.lehmann@tu- stephan.rein@tu- clemens.guehmann@tu- berlin.de berlin.de berlin.de Wavelet Application Group Department of Energy and Automation Technology Chair of Electronic Measurement and Diagnostic Technology Technische Universität Berlin ABSTRACT for using just a few kilobytes of RAM, the source data must This paper describes a free filesystem for external flash mem- be accessible. Another memory intensive task concerns long- ory to be employed with low-complexity sensor nodes. The term sensor logs. system uses a standard secure digital (SD) card that can be easily connected to the serial port interface (SPI) or any A cost effective solution of this memory problem could be general input/output port of the sensor’s processor. The external flash memory. Flash memory is non-volatile and filesystem is evaluated with SD- cards used in SPI mode and therefore power failure safe. Flash memory can be obtained achieves an average random write throughput of about 40 either as raw flash or as standard flash devices such as USB- kByte/sec. For random write access throughputs larger than sticks or SD- cards. Raw flashes are pure flash chips which 400 kByte/sec are achieved. The filesystem allows for stor- do not provide a controller unit for wear levelling- that is, age of large amounts of sensor or program data and can assist a technique for prolonging the service life of the erasable more memory expensive algorithms. It requires 7 kByte of storage media - or garbage collection. -
Total Defrag™ 2009
Total Defrag™ 2009 User Manual Paragon Total Defrag™ 2009 2 User Manual CONTENTS Introduction ............................................................................................................................. 3 Key Features ............................................................................................................................ 3 Installation ............................................................................................................................... 3 Minimum System Requirements ....................................................................................................................3 Installation Procedure .....................................................................................................................................4 Basic Concepts ......................................................................................................................... 5 A Hard Disk Layout.........................................................................................................................................5 File Fragmentation...........................................................................................................................................6 Defragmentation ..............................................................................................................................................7 Interface Overview.................................................................................................................. 7 General -
Resources: Free Software
Resources: Free Software Last Updated: 10/28/2011 Online version: http://depts.washington.edu/triolive/wordpress/ttt/freeware Note: These are resources from our TRIO Tech Talk Blog where you can find the latest tech news and interact with other members of the TRIO Community.. Reviews of Free Software The Best Free Software of 2011 http://www.pcmag.com/article2/0,2817,2381528,00.asp PCMAG.COM’s list of 208 of the best free programs for PCs in a wide variety of categories. Best Free Mac Software 2010 http://www.pcmag.com/article2/0,2817,2369639,00.asp PCMAG.COM’s list of 73 of the best free programs for Macs in a wide variety of categories. The Top 100 Free Apps For Your Phone http://www.pcmag.com/article2/0,2817,2356415,00.asp PCMAG.COM’s list of the best free apps for iPhones, Androids, Blackberries and Windows Mobile phones. Security & Utilities Ad-Aware Free Internet Security http://www.lavasoft.com/products/ad_aware_free.php PC Magazine’s Editors’ Choice for free antivirus software for Windows. Rated highly for both finding and removing malware and blocking new infections. CCleaner http://www.piriform.com/CCLEANER A free utility for PC and Mac for optimizing your system, removing clutter and maintaining privacy. Includes tools to clean your registry, manage start-up items and uninstall programs. Recuva http://www.piriform.com/recuva Lost a file because your computer crashed or you accidentally deleted it? Use this free tool for PCs to recover files from your hard drive, recycle bin or memory card. -
Remote Connect 2016
The Convenience of Remote Connect 2016 TOYOTA APP SMARTWATCH GOOGLE AMAZON Remote Connect As a Companion of the Smartphone ASSISTANT ALEXA Toyota Action Toyota Skill Toyota offers an incredible array of convenience and connectivity features. These features now includeGoogle Assistant and Amazon Alexa3 capability – as well as smartwatch integration – for 2018 and later models equipped with Remote Connect². KEY FOB WITH REMOTE FUNCTIONALITY Vehicles equipped with Remote Connect² have key fob13 compatibility for Remote Start1. Connected Services registration will be required to use the complete suite of Remote Connect services, which include Smartphone, Smartwatch, and smart home devices. Audio Plus vehicle key fob functionality is available for up to 3 years. Beyond 3 years requires a subscription. Applicable for select Model Year 2018 through 2020 Remote Connect capable vehicles. Select Model Year 2020 Remote Connect capable vehicles will have functionality for up to 10 years. Premium Audio vehicle key fob functionality is available for up to 10 years. Beyond 10 years requires a subscription. Applicable for select Model Year 2018 through 2020 Remote Connect capable vehicles. Using the key fob to remote start my Toyota: 1. Press the LOCK button on the remote. 2. Press the LOCK button a second time within 1 second. 3. Press the LOCK button again, this time holding it for 3 seconds. The engine will start. Note: Key Fob Remote Start will not function if Connected Services are waived. REMOTE CONNECT EQUIPPED VEHICLES BUILT BEFORE 11/12/18 Remote Connect equipped vehicles built before 11/12/18 were required to have an active Remote Connect trial or paid subscription for the key fob to perform remote start functionality.