diff options
| -rw-r--r-- | fs/nsfs.c | 11 | ||||
| -rw-r--r-- | include/uapi/linux/nsfs.h | 8 |
2 files changed, 16 insertions, 3 deletions
diff --git a/fs/nsfs.c b/fs/nsfs.c index 5d534763c662..1656843e87d2 100644 --- a/fs/nsfs.c +++ b/fs/nsfs.c @@ -7,6 +7,7 @@ #include <linux/seq_file.h> #include <linux/user_namespace.h> #include <linux/nsfs.h> +#include <linux/uaccess.h> static struct vfsmount *nsfs_mnt; @@ -163,7 +164,10 @@ int open_related_ns(struct ns_common *ns, static long ns_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { + struct user_namespace *user_ns; struct ns_common *ns = get_proc_ns(file_inode(filp)); + uid_t __user *argp; + uid_t uid; switch (ioctl) { case NS_GET_USERNS: @@ -174,6 +178,13 @@ static long ns_ioctl(struct file *filp, unsigned int ioctl, return open_related_ns(ns, ns->ops->get_parent); case NS_GET_NSTYPE: return ns->ops->type; + case NS_GET_OWNER_UID: + if (ns->ops->type != CLONE_NEWUSER) + return -EINVAL; + user_ns = container_of(ns, struct user_namespace, ns); + argp = (uid_t __user *) arg; + uid = from_kuid_munged(current_user_ns(), user_ns->owner); + return put_user(uid, argp); default: return -ENOTTY; } diff --git a/include/uapi/linux/nsfs.h b/include/uapi/linux/nsfs.h index 2b48df11056a..1a3ca79f466b 100644 --- a/include/uapi/linux/nsfs.h +++ b/include/uapi/linux/nsfs.h @@ -6,11 +6,13 @@ #define NSIO 0xb7 /* Returns a file descriptor that refers to an owning user namespace */ -#define NS_GET_USERNS _IO(NSIO, 0x1) +#define NS_GET_USERNS _IO(NSIO, 0x1) /* Returns a file descriptor that refers to a parent namespace */ -#define NS_GET_PARENT _IO(NSIO, 0x2) +#define NS_GET_PARENT _IO(NSIO, 0x2) /* Returns the type of namespace (CLONE_NEW* value) referred to by file descriptor */ -#define NS_GET_NSTYPE _IO(NSIO, 0x3) +#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) #endif /* __LINUX_NSFS_H */ |