kernel/exec_domain.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Handling of different ABIs (personalities).
 *
 * We group personalities into execution domains which have their
 * own handlers for kernel entry points, signal mapping, etc...
 *
 * 2001-05-06	Complete rewrite,  Christoph Hellwig (hch@infradead.org)
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/kmod.h>
#include <linux/module.h>
#include <linux/personality.h>
#include <linux/proc_fs.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/syscalls.h>
#include <linux/sysctl.h>
#include <linux/types.h>

#ifdef CONFIG_PROC_FS
static int execdomains_proc_show(struct seq_file *m, void *v)
{
	seq_puts(m, "0-0\tLinux           \t[kernel]\n");
	return 0;
}

static int execdomains_proc_open(struct inode *inode, struct file *file)
{
	return single_open(file, execdomains_proc_show, NULL);
}

static const struct file_operations execdomains_proc_fops = {
	.open		= execdomains_proc_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static int __init proc_execdomains_init(void)
{
	proc_create("execdomains", 0, NULL, &execdomains_proc_fops);
	return 0;
}
module_init(proc_execdomains_init);
#endif

SYSCALL_DEFINE1(personality, unsigned int, personality)
{
	unsigned int old = current->personality;

	if (personality != 0xffffffff)
		set_personality(personality);

	return old;
}