building kernel creates a file with very big size [duplicate]
I am writing a very simple kernel for my simple os here is the code:void start(){ char* video_memory = (char*)0xb8000; *video_memory = 'x';}I use this command to compile: gcc -m32 -fno-pic...
View ArticleTrying to access the memory of a non-kernel process via task_struct
Currently I've written the following short code segment: struct task_struct *task_list; struct mm_struct *mm = task_list->mm;My goal is to take a snapshot of the process during runtime (or while its...
View ArticleHow to run a C/C++/Python script in KERNEL MODE on Windows 10 64Bit [closed]
I'm an infosec researcher, and I've been looking to develop a rootkit so I can analyse flaws in the Windows 10 64bit system to create patches for them.I understand the difference between user and...
View ArticleHow to change the protection of memory address in kernel (Windows)
#pragma warning(disable: 4100)#include "UnexDriver.h" // includes print() and GetKernelProcAddress()LONGLONG someFunction() { return 10;}typedef NTSTATUS(_stdcall* ZwProtectVirtualMemory_t)(IN HANDLE...
View ArticleHow to replace set_fs(KERNEL_DS) for a kernel 5.10.x module driver version
I've been updating a custom module driver to a 5.10.x linux kernel version. My driver adds a layer over a cdc-acm device. To replicate the behavior the next little driver is used.#include...
View ArticleIs it possible to read a userspace file (from kernelspace) using BPF/eBPF?
I know that as a general note files should not be read from kernelspace.However I am interested in looking for keywords in certain files using a BPF program.Ideally I would like the BPF program to be...
View ArticleUndefined reference to in os kernel linking
i have a problem. I making simple OS kernel with this tutorial: http://wiki.osdev.org/Bare_Bones#Linking_the_Kernelbut,if i want to link files boot.o and kernel.o, gcc compiler returns this...
View ArticleHow to fix problem with kernel work in jupyter?
When i starting work with my jupyter notebook, kernel failed with this errorenter image description hereall text error BlockquoteTraceback (most recent call last): File...
View ArticleKernel compilation fails due to PF_MAX > 44
I have a QEMU VM running an image of the Linux kernel 4.14.78.On the host machine (a server with 96 cores), I am trying to compile a new update for the kernel with some changes I have made.To make this...
View Articlescaling floating point variables in the kernel
I am working to port the code of a packet scheduler from OMNet++ to Linux kernel.In the OMNet++ code there is a formula which calculates the average rate change:avg_rate = avg_rate - alpha*(avg_rate -...
View ArticleError building Android kernel: "multiple target patterns"
I attempted to build a fresh kernel for Nexus 5X following Google's instructions on this pageBuild system: Ubuntu 14.04 x86_64Target system: MTC19T/bullhead (Actually any marshmallow version on...
View ArticleLoop through linked list in kernel space
I'm trying to loop over vma's (referenced by the pointer mm) inside of the task_struct. What I'm doing is trying to print some of the attributes of the struct vm_area_struct (specifically, I'm trying...
View ArticleAccessing memory causes system to freeze
I'm trying to read the values from memory of a process according to their vma's. However, whenever I try to access these locations en masse the system hangs and then crashes.void print_mmap(struct...
View ArticleWhere is there an understandable documentation for the wdm.h c header
I was wondering if there was a possible way to embed regular c/c++ inside a windows kernel mode driver. I've been doing some research and it seems pretty impossible, considering that the print function...
View ArticleVirtualbox 6.1.10, Ubuntu 20.04 bad return status build on kernel 5.8.0,...
Not so much as a question as a documentation.This is regarding a failing apt-get install or update related to virtualbox 6.1.10, Ubuntu 20.04, and virtualbox-dkms package failing to build.I had an...
View ArticleHow to implement a system call that could check if itself has been...
I have just stepped into the kernel world and would like to add some system calls. My goal is to add a system call that lets me check if it executed (without looking at the kernel log). However, I have...
View ArticleLoadable Kernel Module Programming and System Call Interception
Assume that we want to intercept the exit system call and print a message on the console when any process invokes it. In order to do this, we have to write our own fake exit system call, then make the...
View Articlecopy_from_user in conjunction with vm_area_struct
I'm trying to copy vma's (memory) from a process in user space into a process in kernel space using copy_from_user(). The arguments for copy_from_user() require that you have two buffers (source &...
View ArticleDo you need a realtime operating system in order to ensure your program is...
Lets say we a running a headless Linux machine and running a program as user or root (eg reading SPI data from a sensor, listening for http requests) and there is reason to believe there is almost...
View Articlein /proc/pid/limits where the hard limit value comes from?
I didn't set the hard limit value in /etc/security/limits.d/<xx.conf> and /etc/security/limits.conf.There's only soft limit value 4096 set.Then I go to /proc/, and cat the limits. I saw 31839 is...
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