가상메모리 영역의 정보와 파일의 이름을 출력하려고 합니다

#include <linux/kernel.h> 
#include <linux/module.h>
#include <sys/syscall.h>
#include <asm/uaccess h>
#include <linux/sched.h>
#include <linux/mm.h>
 
#define __NR_getmeminfo 334
 
asmlinkage int (*saved_entry) (void);
void **sys_call_table;
 
asmlinkage int sys_getmeminfo(int pid)
{
	struct task_struct *t;
	struct mm_struct *mm;
	struct vm_area_struct *mmap;
	struct file *file;
 
	char *filename;
	char *buf;
 
	t=pid_task(find_vpid(pid), PIDTYPE_PID);
	if(t == NULL){
		printk(“Cannot find PID from user program\n”);
		return 0;
	}
	mm = t->active_mm;
	mmap = mm->mmap;
	buf = kmalloc(512, GFP_KERNEL);
 
	while(mmap) {
		printk(“%08lx - %08lx”, mmap->vm_start, mmap->vm_end);
		file = mmap->vm_file;
		if(file){
			filename = d_path(&file->f_path, buf, 512);
			printk(“%s \n”, filename);
		}
		else {
			printk(“\n”);
		{
		mmap = mmap->vm_next;
	}
	return 0;
}
int module start(void)
{
	saved entry = sys_call_table[__NR_getmeminfo];
	sys_call_table[__NR_getmeminfo] = sys_getmeminfo;
	return 0;
}
void module_end(void)
{
	sys_call_table[__NR_getmeminfo] = saved_entry;
}
 
 module_init(module_start);
 module_exit(module_end);
 
MODULE_LICENSE(“GPL”);

#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<linux/unistd.h>
#include<errno.h>
#include<sys/syscall.h>
 
#define __NR_getmeminfo 334
 
int main(int argc, char *argv[])
{
	int i, pid;
	pid = atoi(argv[1]);
	i = syscall(__NR_getmeminfo, pid);
 
	return 0;
}