linux/include/linux/pid_namespace.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_PID_NS_H
#define _LINUX_PID_NS_H

#include <linux/sched.h>
#include <linux/bug.h>
#include <linux/mm.h>
#include <linux/workqueue.h>
#include <linux/threads.h>
#include <linux/nsproxy.h>
#include <linux/ns_common.h>
#include <linux/idr.h>

/* MAX_PID_NS_LEVEL is needed for limiting size of 'struct pid' */
#define MAX_PID_NS_LEVEL …

struct fs_pin;

#if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE)
/* modes for vm.memfd_noexec sysctl */
#define MEMFD_NOEXEC_SCOPE_EXEC …
#define MEMFD_NOEXEC_SCOPE_NOEXEC_SEAL …
#define MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED …
#endif

struct pid_namespace { … } __randomize_layout;

extern struct pid_namespace init_pid_ns;

#define PIDNS_ADDING …

#ifdef CONFIG_PID_NS
static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
{ … }

#if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE)
static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns)
{ … }
#else
static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns)
{
	return 0;
}
#endif

extern struct pid_namespace *copy_pid_ns(unsigned long flags,
	struct user_namespace *user_ns, struct pid_namespace *ns);
extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
extern void put_pid_ns(struct pid_namespace *ns);

#else /* !CONFIG_PID_NS */
#include <linux/err.h>

static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
{
	return ns;
}

static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns)
{
	return 0;
}

static inline struct pid_namespace *copy_pid_ns(unsigned long flags,
	struct user_namespace *user_ns, struct pid_namespace *ns)
{
	if (flags & CLONE_NEWPID)
		ns = ERR_PTR(-EINVAL);
	return ns;
}

static inline void put_pid_ns(struct pid_namespace *ns)
{
}

static inline void zap_pid_ns_processes(struct pid_namespace *ns)
{
	BUG();
}

static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
{
	return 0;
}
#endif /* CONFIG_PID_NS */

extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
void pidhash_init(void);
void pid_idr_init(void);

static inline bool task_is_in_init_pid_ns(struct task_struct *tsk)
{ … }

#endif /* _LINUX_PID_NS_H */