我正在尝试按照下面的链接说明为我的OS课程进行自定义系统调用： https://uwnthesis.wordpress.com/2016/12/26/basics-of-making-a-rootkit-from-syscall-to-hook/

我的内核版本是5.3.9。  到目前为止，这是我的代码：  我的.c文件（位于/usr/srclinux-5.3.9）：

#include <linux/syscalls.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/tty.h>
#include <linux/string.h>
#include "pname.h"
asmlinkage long sys_process_name(char* process_name){
    /*placeholder to print full string to tty*/
    char name[32];
    strcpy(name,process_name);

    /*tasklist struct to use*/
    struct task_struct *task;

    /*tty struct*/
    struct tty_struct *my_tty;

    /*get current tty*/
    my_tty = get_current_tty();

    /*<sched.h> library method that iterates through list of processes from task_struct defined above*/
    for_each_process(task){
        printk("Task name: %s.\n",task->comm);
        printk("Task ID: %ld.\n",task->pid);
        printk("Task for compare: %s.\n",name);
        printk("\n");
        /*compares the current process name (defined in task->comm) to the passed in name*/
        if(strcmp(task->comm,name) == 0){
        printk("Process Found!\n");
        /*convert to string and put into name[]*/
        sprintf(name,"PID = %ld\n",(long)task_pid_nr(task));
        /*show result to user that called the syscall*/
        (my_tty->driver->ops->write) (my_tty,name,strlen(name)+1);
        }
    }
    return 0;
}

我的.h文件：

asmlinkage long sys_process_name(char*process_name);

我的Makefile：

obj-y := pname.o

我已将此系统调用包括到我的syscalls_64.tbl和syscalls.h中。

在成功编译了上面的代码之后，我尝试了以下代码来测试syscall testPname.c：

#include <stdio.h>
#include <linux/kernel.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <string.h>
int main(){
char name[32];
puts("Enter process to find");
scanf("%s",name);
strtok(name,"\n");
long int status = syscall(335,name); //syscall number 335 and passing in the string.}
printf("System call returned %ld\n",status);
return 0;
}

但是，当我将一堆printk放入pname.c文件中，并注意到“ char * process_name”从未从我的testPname传递到syscall时，因此从未达到strcmp。我尝试浏览一种将参数传递给系统调用的方法，但未能到达那里。