diff options
| -rw-r--r-- | fs/namespace.c | 21 |
1 files changed, 5 insertions, 16 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 0aa87e55cad9..5e57ed9800f5 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2735,7 +2735,7 @@ static inline struct mount *where_to_mount(const struct path *path, * In all cases the location must not have been unmounted and the * chosen mountpoint must be allowed to be mounted on. For "beneath" * case we also require the location to be at the root of a mount - * that has a parent (i.e. is not a root of some namespace). + * that has something mounted on top of it (i.e. has an overmount). */ static void do_lock_mount(const struct path *path, struct pinned_mountpoint *res, @@ -3528,8 +3528,6 @@ static bool mount_is_ancestor(const struct mount *p1, const struct mount *p2) * @mnt_to: mount under which to mount * @mp: mountpoint of @mnt_to * - * - Make sure that nothing can be mounted beneath the caller's current - * root or the rootfs of the namespace. * - Make sure that the caller can unmount the topmost mount ensuring * that the caller could reveal the underlying mountpoint. * - Ensure that nothing has been mounted on top of @mnt_from before we @@ -3543,7 +3541,7 @@ static bool mount_is_ancestor(const struct mount *p1, const struct mount *p2) */ static int can_move_mount_beneath(const struct mount *mnt_from, const struct mount *mnt_to, - const struct mountpoint *mp) + struct pinned_mountpoint *mp) { struct mount *parent_mnt_to = mnt_to->mnt_parent; @@ -3551,15 +3549,6 @@ static int can_move_mount_beneath(const struct mount *mnt_from, if (mnt_from->overmount) return -EINVAL; - /* - * Mounting beneath the rootfs only makes sense when the - * semantics of pivot_root(".", ".") are used. - */ - if (&mnt_to->mnt == current->fs->root.mnt) - return -EINVAL; - if (parent_mnt_to == current->nsproxy->mnt_ns->root) - return -EINVAL; - if (mount_is_ancestor(mnt_to, mnt_from)) return -EINVAL; @@ -3569,7 +3558,7 @@ static int can_move_mount_beneath(const struct mount *mnt_from, * propagating a copy @c of @mnt_from on top of @mnt_to. This * defeats the whole purpose of mounting beneath another mount. */ - if (propagation_would_overmount(parent_mnt_to, mnt_to, mp)) + if (propagation_would_overmount(parent_mnt_to, mnt_to, mp->mp)) return -EINVAL; /* @@ -3585,7 +3574,7 @@ static int can_move_mount_beneath(const struct mount *mnt_from, * @mnt_from beneath @mnt_to. */ if (check_mnt(mnt_from) && - propagation_would_overmount(parent_mnt_to, mnt_from, mp)) + propagation_would_overmount(parent_mnt_to, mnt_from, mp->mp)) return -EINVAL; return 0; @@ -3694,7 +3683,7 @@ static int do_move_mount(const struct path *old_path, if (mp.parent != over->mnt_parent) over = mp.parent->overmount; - err = can_move_mount_beneath(old, over, mp.mp); + err = can_move_mount_beneath(old, over, &mp); if (err) return err; } |