diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 08c66969d52a..5e73d6626e50 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -111,11 +111,6 @@ static int sysfs_link_sibling(struct sysfs_dirent *sd) /* add new node and rebalance the tree */ rb_link_node(&sd->s_rb, parent, node); rb_insert_color(&sd->s_rb, &sd->s_parent->s_dir.children); - - /* if @sd has ns tag, mark the parent to enable ns filtering */ - if (sd->s_ns) - sd->s_parent->s_flags |= SYSFS_FLAG_HAS_NS; - return 0; } @@ -135,13 +130,6 @@ static void sysfs_unlink_sibling(struct sysfs_dirent *sd) sd->s_parent->s_dir.subdirs--; rb_erase(&sd->s_rb, &sd->s_parent->s_dir.children); - - /* - * Either all or none of the children have tags. Clearing HAS_NS - * when there's no child left is enough to keep the flag synced. - */ - if (RB_EMPTY_ROOT(&sd->s_parent->s_dir.children)) - sd->s_parent->s_flags &= ~SYSFS_FLAG_HAS_NS; } /** @@ -291,6 +279,7 @@ static int sysfs_dentry_delete(const struct dentry *dentry) static int sysfs_dentry_revalidate(struct dentry *dentry, unsigned int flags) { struct sysfs_dirent *sd; + int type; if (flags & LOOKUP_RCU) return -ECHILD; @@ -311,8 +300,13 @@ static int sysfs_dentry_revalidate(struct dentry *dentry, unsigned int flags) goto out_bad; /* The sysfs dirent has been moved to a different namespace */ - if (sd->s_ns && sd->s_ns != sysfs_info(dentry->d_sb)->ns) - goto out_bad; + type = KOBJ_NS_TYPE_NONE; + if (sd->s_parent) { + type = sysfs_ns_type(sd->s_parent); + if (type != KOBJ_NS_TYPE_NONE && + sysfs_info(dentry->d_sb)->ns[type] != sd->s_ns) + goto out_bad; + } mutex_unlock(&sysfs_mutex); out_valid: @@ -432,6 +426,13 @@ int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, struct sysfs_inode_attrs *ps_iattr; int ret; + if (!!sysfs_ns_type(parent_sd) != !!sd->s_ns) { + WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", + sysfs_ns_type(parent_sd) ? "required" : "invalid", + parent_sd->s_name, sd->s_name); + return -EINVAL; + } + sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns); sd->s_parent = sysfs_get(parent_sd); @@ -611,6 +612,13 @@ struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, struct rb_node *node = parent_sd->s_dir.children.rb_node; unsigned int hash; + if (!!sysfs_ns_type(parent_sd) != !!ns) { + WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", + sysfs_ns_type(parent_sd) ? "required" : "invalid", + parent_sd->s_name, name); + return NULL; + } + hash = sysfs_name_hash(name, ns); while (node) { struct sysfs_dirent *sd; @@ -659,6 +667,7 @@ struct sysfs_dirent *sysfs_get_dirent_ns(struct sysfs_dirent *parent_sd, EXPORT_SYMBOL_GPL(sysfs_get_dirent_ns); static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, + enum kobj_ns_type type, const char *name, const void *ns, struct sysfs_dirent **p_sd) { @@ -672,6 +681,7 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, if (!sd) return -ENOMEM; + sd->s_flags |= (type << SYSFS_NS_TYPE_SHIFT); sd->s_ns = ns; sd->s_dir.kobj = kobj; @@ -691,7 +701,33 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, int sysfs_create_subdir(struct kobject *kobj, const char *name, struct sysfs_dirent **p_sd) { - return create_dir(kobj, kobj->sd, name, NULL, p_sd); + return create_dir(kobj, kobj->sd, + KOBJ_NS_TYPE_NONE, name, NULL, p_sd); +} + +/** + * sysfs_read_ns_type: return associated ns_type + * @kobj: the kobject being queried + * + * Each kobject can be tagged with exactly one namespace type + * (i.e. network or user). Return the ns_type associated with + * this object if any + */ +static enum kobj_ns_type sysfs_read_ns_type(struct kobject *kobj) +{ + const struct kobj_ns_type_operations *ops; + enum kobj_ns_type type; + + ops = kobj_child_ns_ops(kobj); + if (!ops) + return KOBJ_NS_TYPE_NONE; + + type = ops->type; + BUG_ON(type <= KOBJ_NS_TYPE_NONE); + BUG_ON(type >= KOBJ_NS_TYPES); + BUG_ON(!kobj_ns_type_registered(type)); + + return type; } /** @@ -701,6 +737,7 @@ int sysfs_create_subdir(struct kobject *kobj, const char *name, */ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) { + enum kobj_ns_type type; struct sysfs_dirent *parent_sd, *sd; int error = 0; @@ -714,7 +751,9 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) if (!parent_sd) return -ENOENT; - error = create_dir(kobj, parent_sd, kobject_name(kobj), ns, &sd); + type = sysfs_read_ns_type(kobj); + + error = create_dir(kobj, parent_sd, type, kobject_name(kobj), ns, &sd); if (!error) kobj->sd = sd; return error; @@ -728,12 +767,13 @@ static struct dentry *sysfs_lookup(struct inode *dir, struct dentry *dentry, struct sysfs_dirent *parent_sd = parent->d_fsdata; struct sysfs_dirent *sd; struct inode *inode; - const void *ns = NULL; + enum kobj_ns_type type; + const void *ns; mutex_lock(&sysfs_mutex); - if (parent_sd->s_flags & SYSFS_FLAG_HAS_NS) - ns = sysfs_info(dir->i_sb)->ns; + type = sysfs_ns_type(parent_sd); + ns = sysfs_info(dir->i_sb)->ns[type]; sd = sysfs_find_dirent(parent_sd, dentry->d_name.name, ns); @@ -1056,15 +1096,15 @@ static int sysfs_readdir(struct file *file, struct dir_context *ctx) struct dentry *dentry = file->f_path.dentry; struct sysfs_dirent *parent_sd = dentry->d_fsdata; struct sysfs_dirent *pos = file->private_data; - const void *ns = NULL; + enum kobj_ns_type type; + const void *ns; + + type = sysfs_ns_type(parent_sd); + ns = sysfs_info(dentry->d_sb)->ns[type]; if (!dir_emit_dots(file, ctx)) return 0; mutex_lock(&sysfs_mutex); - - if (parent_sd->s_flags & SYSFS_FLAG_HAS_NS) - ns = sysfs_info(dentry->d_sb)->ns; - for (pos = sysfs_dir_pos(ns, parent_sd, ctx->pos, pos); pos; pos = sysfs_dir_next_pos(ns, parent_sd, ctx->pos, pos)) { diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index 8c24bce2f4ae..834ec2cdb7a3 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -36,7 +36,7 @@ static const struct super_operations sysfs_ops = { struct sysfs_dirent sysfs_root = { .s_name = "", .s_count = ATOMIC_INIT(1), - .s_flags = SYSFS_DIR, + .s_flags = SYSFS_DIR | (KOBJ_NS_TYPE_NONE << SYSFS_NS_TYPE_SHIFT), .s_mode = S_IFDIR | S_IRUGO | S_IXUGO, .s_ino = 1, }; @@ -77,8 +77,14 @@ static int sysfs_test_super(struct super_block *sb, void *data) { struct sysfs_super_info *sb_info = sysfs_info(sb); struct sysfs_super_info *info = data; + enum kobj_ns_type type; + int found = 1; - return sb_info->ns == info->ns; + for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) { + if (sb_info->ns[type] != info->ns[type]) + found = 0; + } + return found; } static int sysfs_set_super(struct super_block *sb, void *data) @@ -92,7 +98,9 @@ static int sysfs_set_super(struct super_block *sb, void *data) static void free_sysfs_super_info(struct sysfs_super_info *info) { - kobj_ns_drop(KOBJ_NS_TYPE_NET, info->ns); + int type; + for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) + kobj_ns_drop(type, info->ns[type]); kfree(info); } @@ -100,6 +108,7 @@ static struct dentry *sysfs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { struct sysfs_super_info *info; + enum kobj_ns_type type; struct super_block *sb; int error; @@ -107,15 +116,18 @@ static struct dentry *sysfs_mount(struct file_system_type *fs_type, if (!capable(CAP_SYS_ADMIN) && !fs_fully_visible(fs_type)) return ERR_PTR(-EPERM); - if (!kobj_ns_current_may_mount(KOBJ_NS_TYPE_NET)) - return ERR_PTR(-EPERM); + for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) { + if (!kobj_ns_current_may_mount(type)) + return ERR_PTR(-EPERM); + } } info = kzalloc(sizeof(*info), GFP_KERNEL); if (!info) return ERR_PTR(-ENOMEM); - info->ns = kobj_ns_grab_current(KOBJ_NS_TYPE_NET); + for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) + info->ns[type] = kobj_ns_grab_current(type); sb = sget(fs_type, sysfs_test_super, sysfs_set_super, flags, info); if (IS_ERR(sb) || sb->s_fs_info != info) diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index 1a23681b8179..3ae3f1bf1a09 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -28,6 +28,7 @@ static int sysfs_do_create_link_sd(struct sysfs_dirent *parent_sd, 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 || !parent_sd); @@ -51,15 +52,29 @@ static int sysfs_do_create_link_sd(struct sysfs_dirent *parent_sd, if (!sd) goto out_put; - sd->s_ns = target_sd->s_ns; + ns_type = sysfs_ns_type(parent_sd); + if (ns_type) + sd->s_ns = target_sd->s_ns; sd->s_symlink.target_sd = target_sd; target_sd = NULL; /* reference is now owned by the symlink */ sysfs_addrm_start(&acxt); - if (warn) - error = sysfs_add_one(&acxt, sd, parent_sd); - else - error = __sysfs_add_one(&acxt, sd, parent_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, parent_sd); + else + error = __sysfs_add_one(&acxt, sd, parent_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) @@ -149,7 +164,7 @@ void sysfs_delete_link(struct kobject *kobj, struct kobject *targ, * sysfs_remove_dir() for details. */ spin_lock(&sysfs_symlink_target_lock); - if (targ->sd) + if (targ->sd && sysfs_ns_type(kobj->sd)) ns = targ->sd->s_ns; spin_unlock(&sysfs_symlink_target_lock); sysfs_hash_and_remove(kobj->sd, name, ns); diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index e3aea92ebfa3..0af09fbfb3f6 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -90,8 +90,11 @@ struct sysfs_dirent { #define SYSFS_COPY_NAME (SYSFS_DIR | SYSFS_KOBJ_LINK) #define SYSFS_ACTIVE_REF (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR) -#define SYSFS_FLAG_MASK ~SYSFS_TYPE_MASK -#define SYSFS_FLAG_HAS_NS 0x01000 +/* identify any namespace tag on sysfs_dirents */ +#define SYSFS_NS_TYPE_MASK 0xf00 +#define SYSFS_NS_TYPE_SHIFT 8 + +#define SYSFS_FLAG_MASK ~(SYSFS_NS_TYPE_MASK|SYSFS_TYPE_MASK) #define SYSFS_FLAG_REMOVED 0x02000 static inline unsigned int sysfs_type(struct sysfs_dirent *sd) @@ -99,6 +102,15 @@ static inline unsigned int sysfs_type(struct sysfs_dirent *sd) return sd->s_flags & SYSFS_TYPE_MASK; } +/* + * Return any namespace tags on this dirent. + * enum kobj_ns_type is defined in linux/kobject.h + */ +static inline enum kobj_ns_type sysfs_ns_type(struct sysfs_dirent *sd) +{ + return (sd->s_flags & SYSFS_NS_TYPE_MASK) >> SYSFS_NS_TYPE_SHIFT; +} + #ifdef CONFIG_DEBUG_LOCK_ALLOC #define sysfs_dirent_init_lockdep(sd) \ @@ -143,13 +155,12 @@ struct sysfs_addrm_cxt { */ /* - * Each sb is associated with one namespace tag, currently the network - * namespace of the task which mounted this sysfs instance. If multiple - * tags become necessary, make the following an array and compare - * sysfs_dirent tag against every entry. + * Each sb is associated with a set of namespace tags (i.e. + * the network namespace of the task which mounted this sysfs + * instance). */ struct sysfs_super_info { - void *ns; + void *ns[KOBJ_NS_TYPES]; }; #define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info)) extern struct sysfs_dirent sysfs_root; diff --git a/lib/kobject.c b/lib/kobject.c index 7a1c203083eb..5b4b8886435e 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -30,14 +30,11 @@ const void *kobject_namespace(struct kobject *kobj) { const struct kobj_ns_type_operations *ns_ops = kobj_ns_ops(kobj); - const void *ns; if (!ns_ops || ns_ops->type == KOBJ_NS_TYPE_NONE) return NULL; - ns = kobj->ktype->namespace(kobj); - WARN_ON(!ns); /* @kobj in a namespace is required to have !NULL tag */ - return ns; + return kobj->ktype->namespace(kobj); } /*