1 // SPDX-License-Identifier: GPL-2.0
36  * Carries the invalid idmapping of a full 0-4294967295 {g,u}id range.
45  * initial_idmapping - check whether this is the initial mapping
59  * make_vfsuid - map a filesystem kuid according to an idmapping
93 	if (uid == (uid_t)-1)  in make_vfsuid()
95 	return VFSUIDT_INIT_RAW(map_id_down(&idmap->uid_map, uid));  in make_vfsuid()
100  * make_vfsgid - map a filesystem kgid according to an idmapping
132 	if (gid == (gid_t)-1)  in make_vfsgid()
134 	return VFSGIDT_INIT_RAW(map_id_down(&idmap->gid_map, gid));  in make_vfsgid()
139  * from_vfsuid - map a vfsuid into the filesystem idmapping
145  * order to e.g. write @vfsuid to inode->i_uid.
158 	uid = map_id_up(&idmap->uid_map, __vfsuid_val(vfsuid));  in from_vfsuid()
159 	if (uid == (uid_t)-1)  in from_vfsuid()
168  * from_vfsgid - map a vfsgid into the filesystem idmapping
174  * order to e.g. write @vfsgid to inode->i_gid.
187 	gid = map_id_up(&idmap->gid_map, __vfsgid_val(vfsgid));  in from_vfsgid()
188 	if (gid == (gid_t)-1)  in from_vfsgid()
198  * vfsgid_in_group_p() - check whether a vfsuid matches the caller's groups
221 	struct uid_gid_extent *forward, *reverse;  in copy_mnt_idmap()  local
222 	u32 nr_extents = READ_ONCE(map_from->nr_extents);  in copy_mnt_idmap()
230 	 * then we might end up with inconsistent data. So just don't do  in copy_mnt_idmap()
234 		return -EINVAL;  in copy_mnt_idmap()
248 	forward = kmemdup_array(map_from->forward, nr_extents,  in copy_mnt_idmap()
252 		return -ENOMEM;  in copy_mnt_idmap()
254 	reverse = kmemdup_array(map_from->reverse, nr_extents,  in copy_mnt_idmap()
257 	if (!reverse) {  in copy_mnt_idmap()
259 		return -ENOMEM;  in copy_mnt_idmap()
267 	map_to->forward = forward;  in copy_mnt_idmap()
268 	map_to->reverse = reverse;  in copy_mnt_idmap()
269 	map_to->nr_extents = nr_extents;  in copy_mnt_idmap()
275 	if (idmap->uid_map.nr_extents > UID_GID_MAP_MAX_BASE_EXTENTS) {  in free_mnt_idmap()
276 		kfree(idmap->uid_map.forward);  in free_mnt_idmap()
277 		kfree(idmap->uid_map.reverse);  in free_mnt_idmap()
279 	if (idmap->gid_map.nr_extents > UID_GID_MAP_MAX_BASE_EXTENTS) {  in free_mnt_idmap()
280 		kfree(idmap->gid_map.forward);  in free_mnt_idmap()
281 		kfree(idmap->gid_map.reverse);  in free_mnt_idmap()
293 		return ERR_PTR(-ENOMEM);  in alloc_mnt_idmap()
295 	refcount_set(&idmap->count, 1);  in alloc_mnt_idmap()
296 	ret = copy_mnt_idmap(&mnt_userns->uid_map, &idmap->uid_map);  in alloc_mnt_idmap()
298 		ret = copy_mnt_idmap(&mnt_userns->gid_map, &idmap->gid_map);  in alloc_mnt_idmap()
307  * mnt_idmap_get - get a reference to an idmapping
317 		refcount_inc(&idmap->count);  in mnt_idmap_get()
324  * mnt_idmap_put - put a reference to an idmapping
327  * If this is a non-initial idmapping, put the reference count when a mount is
333 	    refcount_dec_and_test(&idmap->count))  in mnt_idmap_put()