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-rw-r--r--fs/sysfs/dir.c92
-rw-r--r--fs/sysfs/mount.c24
-rw-r--r--fs/sysfs/symlink.c26
-rw-r--r--fs/sysfs/sysfs.h25
-rw-r--r--include/linux/sysfs.h6
-rw-r--r--lib/kobject.c27
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)
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