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Memory Protection Extensions
Intel MPX (Memory Protection Extensions) are a discontinued set of extensions to the x86 instruction set architecture. With compiler, runtime library and operating system support, Intel MPX claimed to enhance security to software by checking pointer references whose normal compile-time intentions are maliciously exploited at runtime due to buffer overflows. In practice, there have been too many flaws discovered in the design for it to be useful, and support has been deprecated or removed from most compilers and operating systems. Intel has listed MPX as removed in 2019 and onward hardware in section 2.5 of its Intel® 64 and IA-32 Architectures Software Developer's Manual Volume 1. Extensions Intel MPX introduces new bounds registers, and new instruction set extensions that operate on these registers. Additionally, there is a new set of "bound tables" that store bounds beyond what can fit in the bounds registers. MPX uses four new 128-bit bounds registers, BND0 to BND3, each st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Instruction Set Architecture
In computer science, an instruction set architecture (ISA) is an abstract model that generally defines how software controls the CPU in a computer or a family of computers. A device or program that executes instructions described by that ISA, such as a central processing unit (CPU), is called an ''implementation'' of that ISA. In general, an ISA defines the supported instructions, data types, registers, the hardware support for managing main memory, fundamental features (such as the memory consistency, addressing modes, virtual memory), and the input/output model of implementations of the ISA. An ISA specifies the behavior of machine code running on implementations of that ISA in a fashion that does not depend on the characteristics of that implementation, providing binary compatibility between implementations. This enables multiple implementations of an ISA that differ in characteristics such as performance, physical size, and monetary cost (among other things), but t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel C++ Compiler
Intel oneAPI DPC++/C++ Compiler and Intel C++ Compiler Classic (deprecated icc and icl is in Intel OneAPI HPC toolkit) are Intel’s C, C++, SYCL, and Data Parallel C++ (DPC++) compilers for Intel processor-based systems, available for Windows, Linux, and macOS operating systems. Overview Intel oneAPI DPC++/C++ Compiler is available for Windows and Linux and supports compiling C, C++, SYCL, and Data Parallel C++ (DPC++) source, targeting Intel IA-32, Intel 64 (aka x86-64), Core, Xeon, and Xeon Scalable processors, as well as GPUs including Intel Processor Graphics Gen9 and above, Intel Xe architecture, and Intel Programmable Acceleration Card with Intel Arria 10 GX FPGA. Like Intel C++ Compiler Classic, it also supports the Microsoft Visual Studio and Eclipse IDE development environments, and supports threading via Intel oneAPI Threading Building Blocks, OpenMP, and native threads. DPC++ builds on the SYCL specification from The Khronos Group. It is designed to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meltdown (security Vulnerability)
Meltdown is one of the two original speculative execution CPU vulnerabilities (the other being Spectre). Meltdown affects Intel x86 microprocessors, IBM Power microprocessors, and some ARM-based microprocessors. It allows a rogue process to read all memory, even when it is not authorized to do so. Meltdown affects a wide range of systems. At the time of disclosure (2018), this included all devices running any but the most recent and patched versions of iOS, Linux, macOS, or Windows. Accordingly, many servers and cloud services were impacted, as well as a potential majority of smart devices and embedded devices using ARM-based processors (mobile devices, smart TVs, printers and others), including a wide range of networking equipment. A purely software workaround to Meltdown has been assessed as slowing computers between 5 and 30 percent in certain specialized workloads, although companies responsible for software correction of the exploit reported minimal impact from g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectre (security Vulnerability)
Spectre is one of the speculative execution CPU vulnerabilities which involve side-channel attacks. These affect modern microprocessors that perform branch prediction and other forms of speculative execution. On most processors, the speculative execution resulting from a branch misprediction may leave observable side effects that may reveal private data to attackers. For example, if the pattern of memory accesses performed by such speculative execution depends on private data, the resulting state of the data cache constitutes a side channel through which an attacker may be able to extract information about the private data using a timing attack. In addition to vulnerabilities associated with installed applications, JIT engines used for JavaScript were found to be vulnerable. A website can read data stored in the browser for another website, or the browser's memory itself. Two Common Vulnerabilities and Exposures records related to Spectre, (bounds check bypass, Spect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software Guard Extensions
Intel Software Guard Extensions (SGX) is a set of instruction codes implementing trusted execution environment that are built into some Intel central processing units (CPUs). They allow user-level and operating system code to define protected private regions of memory, called ''enclaves''. SGX is designed to be useful for implementing secure remote computation, secure web browsing, and digital rights management (DRM). Other applications include concealment of proprietary algorithms and of encryption keys. SGX involves encryption by the CPU of a portion of memory (the ''enclave''). Data and code originating in the enclave are decrypted on the fly ''within'' the CPU, protecting them from being examined or read by other code, including code running at higher privilege levels such as the operating system and any underlying hypervisors. While this can mitigate many kinds of attacks, it does not protect against side-channel attacks. A pivot by Intel in 2021 resulted in the deprecati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transactional Synchronization Extensions
Transactional Synchronization Extensions (TSX), also called Transactional Synchronization Extensions New Instructions (TSX-NI), is an extension to the x86 instruction set architecture (ISA) that adds hardware transactional memory support, speeding up execution of multi-threaded software through lock elision. According to different benchmarks, TSX/TSX-NI can provide around 40% faster applications execution in specific workloads, and 4–5 times more database transactions per second (TPS). TSX/TSX-NI was documented by Intel in February 2012, and debuted in June 2013 on selected Intel microprocessors based on the Haswell microarchitecture. Haswell processors below 45xx as well as R-series and K-series (with unlocked multiplier) SKUs do not support TSX/TSX-NI. In August 2014, Intel announced a bug in the TSX/TSX-NI implementation on current steppings of Haswell, Haswell-E, Haswell-EP and early Broadwell CPUs, which resulted in disabling the TSX/TSX-NI feature on affected CPUs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flexible Array Member
C struct data types may end with a flexible array member with no specified size: struct vectord ; Typically, such structures serve as the header in a larger, variable memory allocation: struct vectord *vector = malloc(...); vector->len = ...; for (int i = 0; i len; i++) vector->arr = ...; // transparently uses the right type (double) Effect on struct size and padding The sizeof operator on such a struct gives the size of the structure as if the flexible array member were empty. This may include padding added to accommodate the flexible member; the compiler is also free to re-use such padding as part of the array itself. It is common to allocate sizeof(struct) + ''array_len''*sizeof(''array element'') bytes. This is not wrong, but it may allocate a few more bytes than necessary: the compiler may be re-purposing some of the padding that is included in sizeof(struct). Should this be a concern, macros are available to compute the minimum size while ensuring th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C (programming Language)
C (''pronounced'' '' – like the letter c'') is a general-purpose programming language. It was created in the 1970s by Dennis Ritchie and remains very widely used and influential. By design, C's features cleanly reflect the capabilities of the targeted Central processing unit, CPUs. It has found lasting use in operating systems code (especially in Kernel (operating system), kernels), device drivers, and protocol stacks, but its use in application software has been decreasing. C is commonly used on computer architectures that range from the largest supercomputers to the smallest microcontrollers and embedded systems. A successor to the programming language B (programming language), B, C was originally developed at Bell Labs by Ritchie between 1972 and 1973 to construct utilities running on Unix. It was applied to re-implementing the kernel of the Unix operating system. During the 1980s, C gradually gained popularity. It has become one of the most widely used programming langu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AddressSanitizer
A code sanitizer is a programming tool that detects bugs in the form of undefined or suspicious behavior by a compiler inserting instrumentation code at runtime. The class of tools was first introduced by Google's AddressSanitizer (or ASan) of 2012, which uses directly mapped shadow memory to detect memory corruption such as buffer overflows or accesses to a dangling pointer (use-after-free). AddressSanitizer Google's ASan, introduced in 2012, uses a shadow memory scheme to detect memory bugs. It is available in: * Clang (starting from version 3.1) * GCC (starting from version 4.8) * Xcode (starting from version 7.0) * MSVC (widely available starting from version 16.9). On average, the instrumentation increases processing time by about 73% and memory usage by 240%. There is a hardware-accelerated ASan called HWAsan available for AArch64 and (in a limited fashion) x86_64. AddressSanitizer does not detect any uninitialized memory reads (but this is detected by MemorySanitizer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft
Microsoft Corporation is an American multinational corporation and technology company, technology conglomerate headquartered in Redmond, Washington. Founded in 1975, the company became influential in the History of personal computers#The early 1980s and home computers, rise of personal computers through software like Windows, and the company has since expanded to Internet services, cloud computing, video gaming and other fields. Microsoft is the List of the largest software companies, largest software maker, one of the Trillion-dollar company, most valuable public U.S. companies, and one of the List of most valuable brands, most valuable brands globally. Microsoft was founded by Bill Gates and Paul Allen to develop and sell BASIC interpreters for the Altair 8800. It rose to dominate the personal computer operating system market with MS-DOS in the mid-1980s, followed by Windows. During the 41 years from 1980 to 2021 Microsoft released 9 versions of MS-DOS with a median frequen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft Visual Studio 2015
Visual Studio is an integrated development environment (IDE) developed by Microsoft. It is used to develop computer programs including web site, websites, web apps, web services and mobile apps. Visual Studio uses Microsoft software development platforms including Windows API, Windows Forms, Windows Presentation Foundation (WPF), Microsoft Store and Microsoft Silverlight. It can produce both machine code, native code and managed code. Visual Studio includes a code editor supporting IntelliSense (the code completion component) as well as code refactoring. The integrated debugger works as both a source-level debugger and as a machine-level debugger. Other built-in tools include a Profiling (computer programming), code profiler, designer for building GUI applications, web designer, class (computing), class designer, and database schema designer. It accepts plug-ins that expand the functionality at almost every level—including adding support for source control systems (like Subver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
