Commit cdab6ba8 authored by Jakub Kicinski's avatar Jakub Kicinski Committed by Daniel Borkmann
Browse files

nsfs: generalize ns_get_path() for path resolution with a task 



ns_get_path() takes struct task_struct and proc_ns_ops as its
parameters.  For path resolution directly from a namespace,
e.g. based on a networking device's net name space, we need
more flexibility.  Add a ns_get_path_cb() helper which will
allow callers to use any method of obtaining the name space
reference.  Convert ns_get_path() to use ns_get_path_cb().

Following patches will bring a networking user.

CC: Eric W. Biederman <ebiederm@xmission.com>
Suggested-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
parent ad8ad79f

fs/nsfs.c

+26 −3
Original line number Diff line number Diff line
@@ -103,14 +103,14 @@ slow: 
	goto got_it;

}



void *ns_get_path(struct path *path, struct task_struct *task,

			const struct proc_ns_operations *ns_ops)

void *ns_get_path_cb(struct path *path, ns_get_path_helper_t *ns_get_cb,

		     void *private_data)

{

	struct ns_common *ns;

	void *ret;



again:

	ns = ns_ops->get(task);

	ns = ns_get_cb(private_data);

	if (!ns)

		return ERR_PTR(-ENOENT);
@@ -120,6 +120,29 @@ again: 
	return ret;

}



struct ns_get_path_task_args {

	const struct proc_ns_operations *ns_ops;

	struct task_struct *task;

};



static struct ns_common *ns_get_path_task(void *private_data)

{

	struct ns_get_path_task_args *args = private_data;



	return args->ns_ops->get(args->task);

}



void *ns_get_path(struct path *path, struct task_struct *task,

		  const struct proc_ns_operations *ns_ops)

{

	struct ns_get_path_task_args args = {

		.ns_ops	= ns_ops,

		.task	= task,

	};



	return ns_get_path_cb(path, ns_get_path_task, &args);

}



int open_related_ns(struct ns_common *ns,

		   struct ns_common *(*get_ns)(struct ns_common *ns))

{

include/linux/proc_ns.h

+3 −0
Original line number Diff line number Diff line
@@ -78,6 +78,9 @@ extern struct file *proc_ns_fget(int fd); 
#define get_proc_ns(inode) ((struct ns_common *)(inode)->i_private)

extern void *ns_get_path(struct path *path, struct task_struct *task,

			const struct proc_ns_operations *ns_ops);

typedef struct ns_common *ns_get_path_helper_t(void *);

extern void *ns_get_path_cb(struct path *path, ns_get_path_helper_t ns_get_cb,

			    void *private_data);



extern int ns_get_name(char *buf, size_t size, struct task_struct *task,

			const struct proc_ns_operations *ns_ops);

CRA Git | Maintained and supported by SUSTech CRA and CCSE