diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index f71246bebfe4..a7ac78f8e67a 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -28,6 +28,7 @@ static int sysfs_do_create_link(struct kobject *kobj, struct kobject *target, struct sysfs_dirent *target_sd = NULL; struct sysfs_dirent *sd = NULL; struct sysfs_addrm_cxt acxt; + enum kobj_ns_type ns_type; int error; BUG_ON(!name); @@ -58,16 +59,29 @@ static int sysfs_do_create_link(struct kobject *kobj, struct kobject *target, if (!sd) goto out_put; - if (sysfs_ns_type(parent_sd)) + ns_type = sysfs_ns_type(parent_sd); + if (ns_type) sd->s_ns = target->ktype->namespace(target); sd->s_symlink.target_sd = target_sd; target_sd = NULL; /* reference is now owned by the symlink */ sysfs_addrm_start(&acxt, parent_sd); - if (warn) - error = sysfs_add_one(&acxt, sd); - else - error = __sysfs_add_one(&acxt, sd); + /* Symlinks must be between directories with the same ns_type */ + if (!ns_type || + (ns_type == sysfs_ns_type(sd->s_symlink.target_sd->s_parent))) { + if (warn) + error = sysfs_add_one(&acxt, sd); + else + error = __sysfs_add_one(&acxt, sd); + } else { + error = -EINVAL; + WARN(1, KERN_WARNING + "sysfs: symlink across ns_types %s/%s -> %s/%s\n", + parent_sd->s_name, + sd->s_name, + sd->s_symlink.target_sd->s_parent->s_name, + sd->s_symlink.target_sd->s_name); + } sysfs_addrm_finish(&acxt); if (error) @@ -122,7 +136,7 @@ void sysfs_delete_link(struct kobject *kobj, struct kobject *targ, { const void *ns = NULL; spin_lock(&sysfs_assoc_lock); - if (targ->sd) + if (targ->sd && sysfs_ns_type(kobj->sd)) ns = targ->sd->s_ns; spin_unlock(&sysfs_assoc_lock); sysfs_hash_and_remove(kobj->sd, ns, name);