Preface: The vmalloc() function works in a similar fashion to kmalloc(), except it allocates memory that is only virtually contiguous and not necessarily physically contiguous. Background: In the kernel, ION supports multiple clients, one for each driver that uses the ION functionality. A kernel driver calls the following function to obtain an ION client handle:…

Preface: The term vanilla script is used to refer to the pure JavaScript (or we can say plain JavaScript) without any type of additional library. Background: Pure JS implementation of secp256k1 signing, verification, recovery ECDSA. The code works as-is both in browsers and NodeJS, without the need of a bundler. See this link for details…

Preface: Companies like SlideShare, Airbnb, CrunchBase, Bloomberg, Dribble, Shopify, and GitHub have trusted Ruby on Rails and used the framework in their applications. Background: Ruby is an open source, object oriented language that was developed in the mid-90s. Since it is a scripting language. Ruby doesn’t talk to the hardware directly. Rather, it is written…

Preface: In 2021, Linux has been one of the most popular software packages for client devices. According to Digital TV Europe, 800 million set-top boxes are powered by this platform worldwide. Background: The LinuxTV project is an informal group of volunteers who develop software regarding digital television for the Linux kernel-based operating systems. The community…

Preface: Bounds checking is a compiler-based technique that adds run-time bounds information for each allocated block of memory, and checks all pointers against those at run- time. For C and C++, bounds checking can be performed at pointer calculation time or at dereference time. Background: The calloc () function allocates memory for an array of…

Quote: A technical discussion on devblogs.microsoft.com – https://devblogs.microsoft.com/oldnewthing/20200113-00/?p=103322This is not a vulnerability. In Windows, you can put a file in a directory that the user does not have access to, but if the user can produce the name of the file, they can still access it. This works because Windows by default enables “bypass traversal…

Preface: iSCSI is popular in the implementation of SAN systems because of their block level storage structure. When data arrives at its destination the iSCSI protocol separates the SCSI commands so that the Operating System will see the storage as a local device and allow formatting as usual. Background: iSCSI is a block protocol for…

Preface: Dereferencing a null pointer is undefined behavior, typically abnormal program termination. In some situations, however, dereferencing a null pointer can lead to the execution of arbitrary code. Background: io_uring (previously known as aioring) is a Linux kernel system call interface for storage device asynchronous I/O operations addressing performance issues with similar interfaces provided by…

Preface: Whether it is correct or not, this is a spirit for learning. Background: The critical CVE (CVE-2022-34718 ) impacts Windows TCP/IP, allowing an unauthenticated attacker to send a specially crafted IPv6 packet to Windows node where IPSec is enabled. But the supplier didn’t reveal too many details. My observation: CVE-2021-24074 and CVE-2021-24094 occurred in…

Preface: Failures happen all the time, it’s important to see how to deal with them. Background: Background: The new OLE DB provider is called the Microsoft OLE DB Driver for SQL Server (MSOLEDBSQL). The Microsoft OLE DB Provider for SQL Server (SQLOLEDB) still ships as part of Windows Data Access Components. It isn’t maintained anymore…