diff options
Diffstat (limited to 'kernel/user_namespace.c')
| -rw-r--r-- | kernel/user_namespace.c | 31 |
1 files changed, 19 insertions, 12 deletions
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c index 0b0b95418b16..682f40d5632d 100644 --- a/kernel/user_namespace.c +++ b/kernel/user_namespace.c @@ -238,7 +238,7 @@ EXPORT_SYMBOL(__put_user_ns); struct idmap_key { bool map_up; /* true -> id from kid; false -> kid from id */ u32 id; /* id to find */ - u32 count; /* == 0 unless used with map_id_range_down() */ + u32 count; }; /* @@ -343,16 +343,19 @@ u32 map_id_down(struct uid_gid_map *map, u32 id) * UID_GID_MAP_MAX_BASE_EXTENTS. */ static struct uid_gid_extent * -map_id_up_base(unsigned extents, struct uid_gid_map *map, u32 id) +map_id_range_up_base(unsigned extents, struct uid_gid_map *map, u32 id, u32 count) { unsigned idx; - u32 first, last; + u32 first, last, id2; + + id2 = id + count - 1; /* Find the matching extent */ for (idx = 0; idx < extents; idx++) { first = map->extent[idx].lower_first; last = first + map->extent[idx].count - 1; - if (id >= first && id <= last) + if (id >= first && id <= last && + (id2 >= first && id2 <= last)) return &map->extent[idx]; } return NULL; @@ -363,28 +366,28 @@ map_id_up_base(unsigned extents, struct uid_gid_map *map, u32 id) * Can only be called if number of mappings exceeds UID_GID_MAP_MAX_BASE_EXTENTS. */ static struct uid_gid_extent * -map_id_up_max(unsigned extents, struct uid_gid_map *map, u32 id) +map_id_range_up_max(unsigned extents, struct uid_gid_map *map, u32 id, u32 count) { struct idmap_key key; key.map_up = true; - key.count = 1; + key.count = count; key.id = id; return bsearch(&key, map->reverse, extents, sizeof(struct uid_gid_extent), cmp_map_id); } -u32 map_id_up(struct uid_gid_map *map, u32 id) +u32 map_id_range_up(struct uid_gid_map *map, u32 id, u32 count) { struct uid_gid_extent *extent; unsigned extents = map->nr_extents; smp_rmb(); if (extents <= UID_GID_MAP_MAX_BASE_EXTENTS) - extent = map_id_up_base(extents, map, id); + extent = map_id_range_up_base(extents, map, id, count); else - extent = map_id_up_max(extents, map, id); + extent = map_id_range_up_max(extents, map, id, count); /* Map the id or note failure */ if (extent) @@ -395,6 +398,11 @@ u32 map_id_up(struct uid_gid_map *map, u32 id) return id; } +u32 map_id_up(struct uid_gid_map *map, u32 id) +{ + return map_id_range_up(map, id, 1); +} + /** * make_kuid - Map a user-namespace uid pair into a kuid. * @ns: User namespace that the uid is in @@ -853,9 +861,8 @@ static int sort_idmaps(struct uid_gid_map *map) cmp_extents_forward, NULL); /* Only copy the memory from forward we actually need. */ - map->reverse = kmemdup(map->forward, - map->nr_extents * sizeof(struct uid_gid_extent), - GFP_KERNEL); + map->reverse = kmemdup_array(map->forward, map->nr_extents, + sizeof(struct uid_gid_extent), GFP_KERNEL); if (!map->reverse) return -ENOMEM; |