jprobes for execve and execveat

execute.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char *argv[])
{
	char *newargv[] = { NULL, "-l", NULL };
	char *newenviron[] = { NULL };

	newargv[0] = argv[1];
	execve(argv[1], newargv, newenviron);
	/* execve returns only on error */
	perror("execve");
	return 0;
}

jprobe_example.c

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/kprobes.h>

/* Proxy routine having the same arguments as actual do_execve() routine */
int jdo_execve(struct filename *filename,
		const char __user *const __user *__argv,
		const char __user *const __user *__envp)
{
	pr_info("jprobe: execve: %s\n", filename->name);

	/* Always end with a call to jprobe_return(). */
	jprobe_return();
	return 0;
}

/* Proxy routine having the same arguments as actual do_execveat() routine */
int jdo_execveat(int fd, struct filename *filename,
		const char __user *const __user *__argv,
		const char __user *const __user *__envp,
		int flags)
{
	pr_info("jprobe: execveat: %s\n", filename->name);

	/* Always end with a call to jprobe_return(). */
	jprobe_return();
	return 0;
}

static struct jprobe jprobe_execve = {
	.entry			= jdo_execve,
	.kp = {
		.symbol_name	= "do_execve",
	},
};

static struct jprobe jprobe_execveat = {
	.entry			= jdo_execveat,
	.kp = {
		.symbol_name	= "do_execveat",
	},
};


static int __init jprobe_init(void)
{
	int ret;

	ret = register_jprobe(&jprobe_execve);
	if (ret < 0) {
		pr_info("register_jprobe failed, returned %d\n", ret);
		return -1;
	}
	pr_info("Planted jprobe at %p, handler addr %p\n",
	       jprobe_execve.kp.addr, jprobe_execve.entry);

	ret = register_jprobe(&jprobe_execveat);
	if (ret < 0) {
		pr_info("register_jprobe failed, returned %d\n", ret);
		return -1;
	}
	pr_info("Planted jprobe at %p, handler addr %p\n",
	       jprobe_execveat.kp.addr, jprobe_execveat.entry);
	return 0;
}

static void __exit jprobe_exit(void)
{
	unregister_jprobe(&jprobe_execve);
	pr_info("Unregistered execve jprobe\n");
	unregister_jprobe(&jprobe_execveat);
	pr_info("Unregistered execveat jprobe\n");
}

module_init(jprobe_init)
module_exit(jprobe_exit)
MODULE_LICENSE("GPL");

hello,I have two same machines, both are x86 architecture, ubuntu with kernel version 4.4.131.,when i try to printk "const char __user *const __user *__argv",the one is running,the other kernel panic. if i should change some configs to make program read user space data?