From e3b2cf6e5dba416a03152f299d99982dfe1e861d Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Wed, 1 Apr 2026 12:15:58 +0200 Subject: kernfs: pass struct ns_common instead of const void * for namespace tags kernfs has historically used const void * to pass around namespace tags used for directory-level namespace filtering. The only current user of this is sysfs network namespace tagging where struct net pointers are cast to void *. Replace all const void * namespace parameters with const struct ns_common * throughout the kernfs, sysfs, and kobject namespace layers. This includes the kobj_ns_type_operations callbacks, kobject_namespace(), and all sysfs/kernfs APIs that accept or return namespace tags. Passing struct ns_common is needed because various codepaths require access to the underlying namespace. A struct ns_common can always be converted back to the concrete namespace type (e.g., struct net) via container_of() or to_ns_common() in the reverse direction. This is a preparatory change for switching to ns_id-based directory iteration to prevent a KASLR pointer leak through the current use of raw namespace pointers as hash seeds and comparison keys. Signed-off-by: Christian Brauner --- include/linux/kobject.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/kobject.h') diff --git a/include/linux/kobject.h b/include/linux/kobject.h index c8219505a79f..bcb5d4e32001 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -109,7 +109,7 @@ struct kobject *kobject_get(struct kobject *kobj); struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj); void kobject_put(struct kobject *kobj); -const void *kobject_namespace(const struct kobject *kobj); +const struct ns_common *kobject_namespace(const struct kobject *kobj); void kobject_get_ownership(const struct kobject *kobj, kuid_t *uid, kgid_t *gid); char *kobject_get_path(const struct kobject *kobj, gfp_t flag); @@ -118,7 +118,7 @@ struct kobj_type { const struct sysfs_ops *sysfs_ops; const struct attribute_group **default_groups; const struct kobj_ns_type_operations *(*child_ns_type)(const struct kobject *kobj); - const void *(*namespace)(const struct kobject *kobj); + const struct ns_common *(*namespace)(const struct kobject *kobj); void (*get_ownership)(const struct kobject *kobj, kuid_t *uid, kgid_t *gid); }; -- cgit v1.2.3