[PATCH net-next v3 4/9] sysfs: add sysfs_change_owner()
From: Christian Brauner <hidden>
Date: 2020-02-18 16:30:47
Also in:
linux-pm, lkml
Subsystem:
driver core, kobjects, debugfs and sysfs, filesystems (vfs and infrastructure), the rest · Maintainers:
Greg Kroah-Hartman, "Rafael J. Wysocki", Danilo Krummrich, Alexander Viro, Christian Brauner, Linus Torvalds
Add a helper to change the owner of sysfs objects. This function will be used to correctly account for kobject ownership changes, e.g. when moving network devices between network namespaces. Signed-off-by: Christian Brauner <redacted> --- /* v2 */ - Greg Kroah-Hartman [off-list ref]: - Add comment how ownership of sysfs object is changed. /* v3 */ - Greg Kroah-Hartman [off-list ref]: - Add explicit uid/gid parameters. --- fs/sysfs/file.c | 39 +++++++++++++++++++++++++++++++++++++++ include/linux/sysfs.h | 6 ++++++ 2 files changed, 45 insertions(+)
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index df5107d7b3fd..02f7e852aad4 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c@@ -665,3 +665,42 @@ int sysfs_file_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid) return error; } EXPORT_SYMBOL_GPL(sysfs_file_change_owner); + +/** + * sysfs_change_owner - change owner of the given object. + * @kobj: object. + * @kuid: new owner's kuid + * @kgid: new owner's kgid + */ +int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid) +{ + int error; + const struct kobj_type *ktype; + + if (!kobj->state_in_sysfs) + return -EINVAL; + + error = sysfs_file_change_owner(kobj, kuid, kgid); + if (error) + return error; + + ktype = get_ktype(kobj); + if (ktype) { + struct attribute **kattr; + + for (kattr = ktype->default_attrs; kattr && *kattr; kattr++) { + error = sysfs_file_change_owner_by_name( + kobj, (*kattr)->name, kuid, kgid); + if (error) + return error; + } + + error = sysfs_groups_change_owner(kobj, ktype->default_groups, + kuid, kgid); + if (error) + return error; + } + + return 0; +} +EXPORT_SYMBOL_GPL(sysfs_change_owner);
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index 564a2e57b90a..fa1a37dd0f2b 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h@@ -313,6 +313,7 @@ static inline void sysfs_enable_ns(struct kernfs_node *kn) int sysfs_file_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid); int sysfs_file_change_owner_by_name(struct kobject *kobj, const char *name, kuid_t kuid, kgid_t kgid); +int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid); int sysfs_link_change_owner(struct kobject *kobj, struct kobject *targ, const char *name, kuid_t kuid, kgid_t kgid); int sysfs_groups_change_owner(struct kobject *kobj,
@@ -555,6 +556,11 @@ static inline int sysfs_link_change_owner(struct kobject *kobj, return 0; } +static inline int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid) +{ + return 0; +} + static inline int sysfs_groups_change_owner(struct kobject *kobj, const struct attribute_group **groups, kuid_t kuid, kgid_t kgid)
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2.25.0