aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--fs/sysfs/dir.c88
-rw-r--r--fs/sysfs/mount.c24
-rw-r--r--fs/sysfs/symlink.c27
-rw-r--r--fs/sysfs/sysfs.h25
-rw-r--r--lib/kobject.c5
5 files changed, 122 insertions, 47 deletions
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);
}
/*
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.