Kernel/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-12-29 17:25:38 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

fs: add an ioctl to get the mnt ns id from nsfs

Browse Source 
In order to utilize the listmount() and statmount() extensions that
allow us to call them on different namespaces we need a way to get the
mnt namespace id from user space.  Add an ioctl to nsfs that will allow
us to extract the mnt namespace id in order to make these new extensions
usable.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/180449959d5a756af7306d6bda55f41b9d53e3cb.1719243756.git.josef@toxicpanda.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Josef Bacik 2024-06-24 11:49:50 -04:00 committed by Christian Brauner
parent 71aacb4c8c
commit e8e43a1fcc
No known key found for this signature in database
GPG Key ID: 91C61BC06578DCA2
2 changed files with 16 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
fs/nsfs.c
View File

@ -12,6 +12,7 @@
#include <linux/nsfs.h>
#include <linux/uaccess.h>
#include "mount.h"
#include "internal.h"
static struct vfsmount *nsfs_mnt;
@ -143,6 +144,19 @@ static long ns_ioctl(struct file *filp, unsigned int ioctl,
argp = (uid_t __user *) arg;
uid = from_kuid_munged(current_user_ns(), user_ns->owner);
return put_user(uid, argp);
case NS_GET_MNTNS_ID: {
struct mnt_namespace *mnt_ns;
__u64 __user *idp;
__u64 id;
if (ns->ops->type != CLONE_NEWNS)
return -EINVAL;
mnt_ns = container_of(ns, struct mnt_namespace, ns);
idp = (__u64 __user *)arg;
id = mnt_ns->seq;
return put_user(id, idp);
}
default:
return -ENOTTY;
}

2
include/uapi/linux/nsfs.h
View File

@ -15,5 +15,7 @@
#define NS_GET_NSTYPE _IO(NSIO, 0x3)
/* Get owner UID (in the caller's user namespace) for a user namespace */
#define NS_GET_OWNER_UID _IO(NSIO, 0x4)
/* Get the id for a mount namespace */
#define NS_GET_MNTNS_ID _IO(NSIO, 0x5)
#endif /* __LINUX_NSFS_H */