forked from mirrors/linux
		
	 d7e4f8545b
			
		
	
	
		d7e4f8545b
		
	
	
	
	
		
			
			Currently the kernel uses open code in multiple places to check if a
task is in the root PID namespace with the kind of format:
  if (task_active_pid_ns(current) == &init_pid_ns)
      do_something();
This patch creates a new helper function, task_is_in_init_pid_ns(), it
returns true if a passed task is in the root PID namespace, otherwise
returns false.  So it will be used to replace open codes.
Suggested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
		
	
			
		
			
				
	
	
		
			94 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			94 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef _LINUX_PID_NS_H
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| #define _LINUX_PID_NS_H
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| 
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| #include <linux/sched.h>
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| #include <linux/bug.h>
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| #include <linux/mm.h>
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| #include <linux/workqueue.h>
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| #include <linux/threads.h>
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| #include <linux/nsproxy.h>
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| #include <linux/ns_common.h>
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| #include <linux/idr.h>
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| 
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| /* MAX_PID_NS_LEVEL is needed for limiting size of 'struct pid' */
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| #define MAX_PID_NS_LEVEL 32
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| 
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| struct fs_pin;
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| 
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| struct pid_namespace {
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| 	struct idr idr;
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| 	struct rcu_head rcu;
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| 	unsigned int pid_allocated;
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| 	struct task_struct *child_reaper;
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| 	struct kmem_cache *pid_cachep;
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| 	unsigned int level;
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| 	struct pid_namespace *parent;
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| #ifdef CONFIG_BSD_PROCESS_ACCT
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| 	struct fs_pin *bacct;
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| #endif
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| 	struct user_namespace *user_ns;
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| 	struct ucounts *ucounts;
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| 	int reboot;	/* group exit code if this pidns was rebooted */
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| 	struct ns_common ns;
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| } __randomize_layout;
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| 
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| extern struct pid_namespace init_pid_ns;
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| 
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| #define PIDNS_ADDING (1U << 31)
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| 
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| #ifdef CONFIG_PID_NS
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| static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
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| {
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| 	if (ns != &init_pid_ns)
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| 		refcount_inc(&ns->ns.count);
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| 	return ns;
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| }
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| 
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| extern struct pid_namespace *copy_pid_ns(unsigned long flags,
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| 	struct user_namespace *user_ns, struct pid_namespace *ns);
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| extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
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| extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
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| extern void put_pid_ns(struct pid_namespace *ns);
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| 
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| #else /* !CONFIG_PID_NS */
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| #include <linux/err.h>
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| 
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| static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
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| {
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| 	return ns;
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| }
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| 
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| static inline struct pid_namespace *copy_pid_ns(unsigned long flags,
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| 	struct user_namespace *user_ns, struct pid_namespace *ns)
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| {
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| 	if (flags & CLONE_NEWPID)
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| 		ns = ERR_PTR(-EINVAL);
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| 	return ns;
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| }
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| 
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| static inline void put_pid_ns(struct pid_namespace *ns)
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| {
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| }
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| 
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| static inline void zap_pid_ns_processes(struct pid_namespace *ns)
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| {
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| 	BUG();
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| }
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| 
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| static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
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| {
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| 	return 0;
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| }
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| #endif /* CONFIG_PID_NS */
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| 
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| extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
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| void pidhash_init(void);
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| void pid_idr_init(void);
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| 
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| static inline bool task_is_in_init_pid_ns(struct task_struct *tsk)
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| {
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| 	return task_active_pid_ns(tsk) == &init_pid_ns;
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| }
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| 
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| #endif /* _LINUX_PID_NS_H */
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