diff options
| -rw-r--r-- | fs/sysfs/dir.c | 92 | ||||
| -rw-r--r-- | fs/sysfs/mount.c | 24 | ||||
| -rw-r--r-- | fs/sysfs/symlink.c | 26 | ||||
| -rw-r--r-- | fs/sysfs/sysfs.h | 25 | ||||
| -rw-r--r-- | include/linux/sysfs.h | 6 | ||||
| -rw-r--r-- | lib/kobject.c | 27 |
6 files changed, 83 insertions, 117 deletions
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 5e73d66..b3cf61d 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -279,7 +279,6 @@ 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; @@ -300,13 +299,9 @@ static int sysfs_dentry_revalidate(struct dentry *dentry, unsigned int flags) goto out_bad; /* The sysfs dirent has been moved to a different namespace */ - 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; - } + if (sd->s_parent && (sd->s_parent->s_flags & SYSFS_FLAG_NS) && + sysfs_info(dentry->d_sb)->ns != sd->s_ns) + goto out_bad; mutex_unlock(&sysfs_mutex); out_valid: @@ -423,13 +418,14 @@ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt) int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, struct sysfs_dirent *parent_sd) { + bool has_ns = parent_sd->s_flags & SYSFS_FLAG_NS; struct sysfs_inode_attrs *ps_iattr; int ret; - if (!!sysfs_ns_type(parent_sd) != !!sd->s_ns) { + if (has_ns != (bool)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); + has_ns ? "required" : "invalid", + parent_sd->s_name, sd->s_name); return -EINVAL; } @@ -610,12 +606,13 @@ struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, const void *ns) { struct rb_node *node = parent_sd->s_dir.children.rb_node; + bool has_ns = parent_sd->s_flags & SYSFS_FLAG_NS; unsigned int hash; - if (!!sysfs_ns_type(parent_sd) != !!ns) { + if (has_ns != (bool)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); + has_ns ? "required" : "invalid", + parent_sd->s_name, name); return NULL; } @@ -667,7 +664,6 @@ 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) { @@ -681,7 +677,6 @@ 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; @@ -701,33 +696,7 @@ 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, - 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; + return create_dir(kobj, kobj->sd, name, NULL, p_sd); } /** @@ -737,7 +706,6 @@ static enum kobj_ns_type sysfs_read_ns_type(struct kobject *kobj) */ 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; @@ -751,9 +719,7 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) if (!parent_sd) return -ENOENT; - type = sysfs_read_ns_type(kobj); - - error = create_dir(kobj, parent_sd, type, kobject_name(kobj), ns, &sd); + error = create_dir(kobj, parent_sd, kobject_name(kobj), ns, &sd); if (!error) kobj->sd = sd; return error; @@ -767,13 +733,12 @@ 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; - enum kobj_ns_type type; - const void *ns; + const void *ns = NULL; mutex_lock(&sysfs_mutex); - type = sysfs_ns_type(parent_sd); - ns = sysfs_info(dir->i_sb)->ns[type]; + if (parent_sd->s_flags & SYSFS_FLAG_NS) + ns = sysfs_info(dir->i_sb)->ns; sd = sysfs_find_dirent(parent_sd, dentry->d_name.name, ns); @@ -1029,6 +994,21 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, return sysfs_rename(sd, new_parent_sd, sd->s_name, new_ns); } +/** + * sysfs_enable_ns - enable namespace under a directory + * @sd: directory of interest, should be empty + * + * This is to be called right after @sd is created to enable namespace + * under it. All children of @sd must have non-NULL namespace tags and + * only the ones which match the super_block's tag will be visible. + */ +void sysfs_enable_ns(struct sysfs_dirent *sd) +{ + WARN_ON_ONCE(sysfs_type(sd) != SYSFS_DIR); + WARN_ON_ONCE(!RB_EMPTY_ROOT(&sd->s_dir.children)); + sd->s_flags |= SYSFS_FLAG_NS; +} + /* Relationship between s_mode and the DT_xxx types */ static inline unsigned char dt_type(struct sysfs_dirent *sd) { @@ -1096,15 +1076,15 @@ 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; - enum kobj_ns_type type; - const void *ns; - - type = sysfs_ns_type(parent_sd); - ns = sysfs_info(dentry->d_sb)->ns[type]; + const void *ns = NULL; if (!dir_emit_dots(file, ctx)) return 0; mutex_lock(&sysfs_mutex); + + if (parent_sd->s_flags & SYSFS_FLAG_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 834ec2c..8c24bce 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 | (KOBJ_NS_TYPE_NONE << SYSFS_NS_TYPE_SHIFT), + .s_flags = SYSFS_DIR, .s_mode = S_IFDIR | S_IRUGO | S_IXUGO, .s_ino = 1, }; @@ -77,14 +77,8 @@ 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; - for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) { - if (sb_info->ns[type] != info->ns[type]) - found = 0; - } - return found; + return sb_info->ns == info->ns; } static int sysfs_set_super(struct super_block *sb, void *data) @@ -98,9 +92,7 @@ static int sysfs_set_super(struct super_block *sb, void *data) static void free_sysfs_super_info(struct sysfs_super_info *info) { - int type; - for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) - kobj_ns_drop(type, info->ns[type]); + kobj_ns_drop(KOBJ_NS_TYPE_NET, info->ns); kfree(info); } @@ -108,7 +100,6 @@ 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; @@ -116,18 +107,15 @@ 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); - for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) { - if (!kobj_ns_current_may_mount(type)) - return ERR_PTR(-EPERM); - } + if (!kobj_ns_current_may_mount(KOBJ_NS_TYPE_NET)) + return ERR_PTR(-EPERM); } info = kzalloc(sizeof(*info), GFP_KERNEL); if (!info) return ERR_PTR(-ENOMEM); - for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) - info->ns[type] = kobj_ns_grab_current(type); + info->ns = kobj_ns_grab_current(KOBJ_NS_TYPE_NET); 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 3ae3f1b..c660363 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -28,7 +28,6 @@ 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); @@ -52,29 +51,16 @@ static int sysfs_do_create_link_sd(struct sysfs_dirent *parent_sd, if (!sd) goto out_put; - ns_type = sysfs_ns_type(parent_sd); - if (ns_type) + if (parent_sd->s_flags & SYSFS_FLAG_NS) 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); - /* 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); - } + if (warn) + error = sysfs_add_one(&acxt, sd, parent_sd); + else + error = __sysfs_add_one(&acxt, sd, parent_sd); sysfs_addrm_finish(&acxt); if (error) @@ -164,7 +150,7 @@ void sysfs_delete_link(struct kobject *kobj, struct kobject *targ, * sysfs_remove_dir() for details. */ spin_lock(&sysfs_symlink_target_lock); - if (targ->sd && sysfs_ns_type(kobj->sd)) + if (targ->sd && (kobj->sd->s_flags & SYSFS_FLAG_NS)) 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 0af09fb..e116c21 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -90,11 +90,8 @@ struct sysfs_dirent { #define SYSFS_COPY_NAME (SYSFS_DIR | SYSFS_KOBJ_LINK) #define SYSFS_ACTIVE_REF (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR) -/* 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_MASK ~SYSFS_TYPE_MASK +#define SYSFS_FLAG_NS 0x01000 #define SYSFS_FLAG_REMOVED 0x02000 static inline unsigned int sysfs_type(struct sysfs_dirent *sd) @@ -102,15 +99,6 @@ 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) \ @@ -155,12 +143,13 @@ struct sysfs_addrm_cxt { */ /* - * Each sb is associated with a set of namespace tags (i.e. - * the network namespace of the task which mounted this sysfs - * instance). + * 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. */ struct sysfs_super_info { - void *ns[KOBJ_NS_TYPES]; + void *ns; }; #define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info)) extern struct sysfs_dirent sysfs_root; diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 6695040..362a34d 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -220,6 +220,8 @@ int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target, void sysfs_delete_link(struct kobject *dir, struct kobject *targ, const char *name); +void sysfs_enable_ns(struct sysfs_dirent *sd); + int __must_check sysfs_create_group(struct kobject *kobj, const struct attribute_group *grp); int __must_check sysfs_create_groups(struct kobject *kobj, @@ -353,6 +355,10 @@ static inline void sysfs_delete_link(struct kobject *k, struct kobject *t, { } +static inline void sysfs_enable_ns(struct sysfs_dirent *sd) +{ +} + static inline int sysfs_create_group(struct kobject *kobj, const struct attribute_group *grp) { diff --git a/lib/kobject.c b/lib/kobject.c index 5b4b888..16e9335 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -65,13 +65,17 @@ static int populate_dir(struct kobject *kobj) static int create_dir(struct kobject *kobj) { + const struct kobj_ns_type_operations *ops; int error; error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj)); - if (!error) { - error = populate_dir(kobj); - if (error) - sysfs_remove_dir(kobj); + if (error) + return error; + + error = populate_dir(kobj); + if (error) { + sysfs_remove_dir(kobj); + return error; } /* @@ -80,7 +84,20 @@ static int create_dir(struct kobject *kobj) */ sysfs_get(kobj->sd); - return error; + /* + * If @kobj has ns_ops, its children need to be filtered based on + * their namespace tags. Enable namespace support on @kobj->sd. + */ + ops = kobj_child_ns_ops(kobj); + if (ops) { + BUG_ON(ops->type <= KOBJ_NS_TYPE_NONE); + BUG_ON(ops->type >= KOBJ_NS_TYPES); + BUG_ON(!kobj_ns_type_registered(ops->type)); + + sysfs_enable_ns(kobj->sd); + } + + return 0; } static int get_kobj_path_length(struct kobject *kobj) |
