diff options
| -rw-r--r-- | fs/sysfs/file.c | 41 | ||||
| -rw-r--r-- | include/linux/sysfs.h | 10 |
2 files changed, 51 insertions, 0 deletions
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 4ca936ca3ba4..332cd69b378c 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -571,6 +571,47 @@ static int internal_change_owner(struct kernfs_node *kn, kuid_t kuid, } /** + * sysfs_link_change_owner - change owner of a sysfs file. + * @kobj: object of the kernfs_node the symlink is located in. + * @targ: object of the kernfs_node the symlink points to. + * @name: name of the link. + * @kuid: new owner's kuid + * @kgid: new owner's kgid + * + * This function looks up the sysfs symlink entry @name under @kobj and changes + * the ownership to @kuid/@kgid. The symlink is looked up in the namespace of + * @targ. + * + * Returns 0 on success or error code on failure. + */ +int sysfs_link_change_owner(struct kobject *kobj, struct kobject *targ, + const char *name, kuid_t kuid, kgid_t kgid) +{ + struct kernfs_node *kn = NULL; + int error; + + if (!name || !kobj->state_in_sysfs || !targ->state_in_sysfs) + return -EINVAL; + + error = -ENOENT; + kn = kernfs_find_and_get_ns(kobj->sd, name, targ->sd->ns); + if (!kn) + goto out; + + error = -EINVAL; + if (kernfs_type(kn) != KERNFS_LINK) + goto out; + if (kn->symlink.target_kn->priv != targ) + goto out; + + error = internal_change_owner(kn, kuid, kgid); + +out: + kernfs_put(kn); + return error; +} + +/** * sysfs_file_change_owner - change owner of a sysfs file. * @kobj: object. * @name: name of the file to change. diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index a7884024a911..7e15ebfd750e 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -312,6 +312,8 @@ static inline void sysfs_enable_ns(struct kernfs_node *kn) int sysfs_file_change_owner(struct kobject *kobj, const char *name, 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); #else /* CONFIG_SYSFS */ @@ -532,6 +534,14 @@ static inline int sysfs_file_change_owner(struct kobject *kobj, return 0; } +static inline int sysfs_link_change_owner(struct kobject *kobj, + struct kobject *targ, + const char *name, kuid_t kuid, + kgid_t kgid) +{ + return 0; +} + #endif /* CONFIG_SYSFS */ static inline int __must_check sysfs_create_file(struct kobject *kobj, |