@@ -55,61 +55,109 @@ static struct file_system_type anon_inode_fs_type = {
.kill_sb = kill_anon_super,
};
-/**
- * anon_inode_getfile - creates a new file instance by hooking it up to an
- * anonymous inode, and a dentry that describe the "class"
- * of the file
- *
- * @name: [in] name of the "class" of the new file
- * @fops: [in] file operations for the new file
- * @priv: [in] private data for the new file (will be file's private_data)
- * @flags: [in] flags
- *
- * Creates a new file by hooking it on a single inode. This is useful for files
- * that do not need to have a full-fledged inode in order to operate correctly.
- * All the files created with anon_inode_getfile() will share a single inode,
- * hence saving memory and avoiding code duplication for the file/inode/dentry
- * setup. Returns the newly created file* or an error pointer.
- */
-struct file *anon_inode_getfile(const char *name,
- const struct file_operations *fops,
- void *priv, int flags)
+static struct inode *anon_inode_make_secure_inode(
+ const char *name,
+ const struct inode *context_inode)
{
+ struct inode *inode;
+ const struct qstr qname = QSTR_INIT(name, strlen(name));
+ int error;
+
+ inode = alloc_anon_inode(anon_inode_mnt->mnt_sb);
+ if (IS_ERR(inode))
+ return inode;
+ inode->i_flags &= ~S_PRIVATE;
+ error = security_inode_init_security_anon(
+ inode, &qname, context_inode);
+ if (error) {
+ iput(inode);
+ return ERR_PTR(error);
+ }
+ return inode;
+}
+
+static struct file *_anon_inode_getfile(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags,
+ const struct inode *context_inode,
+ bool secure)
+{
+ struct inode *inode;
struct file *file;
- if (IS_ERR(anon_inode_inode))
- return ERR_PTR(-ENODEV);
+ if (secure) {
+ inode = anon_inode_make_secure_inode(
+ name, context_inode);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ } else {
+ inode = anon_inode_inode;
+ if (IS_ERR(inode))
+ return ERR_PTR(-ENODEV);
+ /*
+ * We know the anon_inode inode count is always
+ * greater than zero, so ihold() is safe.
+ */
+ ihold(inode);
+ }
- if (fops->owner && !try_module_get(fops->owner))
- return ERR_PTR(-ENOENT);
+ if (fops->owner && !try_module_get(fops->owner)) {
+ file = ERR_PTR(-ENOENT);
+ goto err;
+ }
- /*
- * We know the anon_inode inode count is always greater than zero,
- * so ihold() is safe.
- */
- ihold(anon_inode_inode);
- file = alloc_file_pseudo(anon_inode_inode, anon_inode_mnt, name,
+ file = alloc_file_pseudo(inode, anon_inode_mnt, name,
flags & (O_ACCMODE | O_NONBLOCK), fops);
if (IS_ERR(file))
goto err;
- file->f_mapping = anon_inode_inode->i_mapping;
+ file->f_mapping = inode->i_mapping;
file->private_data = priv;
return file;
err:
- iput(anon_inode_inode);
+ iput(inode);
module_put(fops->owner);
return file;
}
-EXPORT_SYMBOL_GPL(anon_inode_getfile);
/**
- * anon_inode_getfd - creates a new file instance by hooking it up to an
- * anonymous inode, and a dentry that describe the "class"
- * of the file
+ * anon_inode_getfile_secure - creates a new file instance by hooking
+ * it up to a new anonymous inode and a
+ * dentry that describe the "class" of the
+ * file. Make it possible to use security
+ * modules to control access to the
+ * new file.
+ *
+ * @name: [in] name of the "class" of the new file
+ * @fops: [in] file operations for the new file
+ * @priv: [in] private data for the new file (will be file's private_data)
+ * @flags: [in] flags
+ * @context_inode [in] inode for additional contextual info to security modules
+ *
+ * Creates a new file by hooking it on an unspecified inode. This is
+ * useful for files that do not need to have a full-fledged filesystem
+ * to operate correctly. All the files created with
+ * anon_inode_getfile_secure() will have distinct inodes, avoiding
+ * code duplication for the file/inode/dentry setup. Returns the
+ * newly created file* or an error pointer.
+ */
+struct file *anon_inode_getfile_secure(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags,
+ const struct inode *context_inode)
+{
+ return _anon_inode_getfile(
+ name, fops, priv, flags, context_inode, true);
+}
+EXPORT_SYMBOL_GPL(anon_inode_getfile_secure);
+
+/**
+ * anon_inode_getfile - creates a new file instance by hooking it up to an
+ * anonymous inode, and a dentry that describe the "class"
+ * of the file
*
* @name: [in] name of the "class" of the new file
* @fops: [in] file operations for the new file
@@ -118,12 +166,23 @@ EXPORT_SYMBOL_GPL(anon_inode_getfile);
*
* Creates a new file by hooking it on a single inode. This is useful for files
* that do not need to have a full-fledged inode in order to operate correctly.
- * All the files created with anon_inode_getfd() will share a single inode,
+ * All the files created with anon_inode_getfile() will share a single inode,
* hence saving memory and avoiding code duplication for the file/inode/dentry
- * setup. Returns new descriptor or an error code.
+ * setup. Returns the newly created file* or an error pointer.
*/
-int anon_inode_getfd(const char *name, const struct file_operations *fops,
- void *priv, int flags)
+struct file *anon_inode_getfile(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags)
+{
+ return _anon_inode_getfile(name, fops, priv, flags, NULL, false);
+}
+EXPORT_SYMBOL_GPL(anon_inode_getfile);
+
+static int _anon_inode_getfd(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags,
+ const struct inode *context_inode,
+ bool secure)
{
int error, fd;
struct file *file;
@@ -133,7 +192,8 @@ int anon_inode_getfd(const char *name, const struct file_operations *fops,
return error;
fd = error;
- file = anon_inode_getfile(name, fops, priv, flags);
+ file = _anon_inode_getfile(name, fops, priv, flags, context_inode,
+ secure);
if (IS_ERR(file)) {
error = PTR_ERR(file);
goto err_put_unused_fd;
@@ -146,6 +206,58 @@ int anon_inode_getfd(const char *name, const struct file_operations *fops,
put_unused_fd(fd);
return error;
}
+
+/**
+ * anon_inode_getfd_secure - creates a new file instance by hooking it
+ * up to a new anonymous inode and a dentry
+ * that describe the "class" of the file.
+ * Make it possible to use security modules
+ * to control access to the new file.
+ *
+ * @name: [in] name of the "class" of the new file
+ * @fops: [in] file operations for the new file
+ * @priv: [in] private data for the new file (will be file's private_data)
+ * @flags: [in] flags
+ * @context_inode [in] inode for additional contextual info to security modules
+ *
+ * Creates a new file by hooking it on an unspecified inode. This is
+ * useful for files that do not need to have a full-fledged filesystem
+ * to operate correctly. All the files created with
+ * anon_inode_getfile_secure() will have distinct inodes, avoiding
+ * code duplication for the file/inode/dentry setup. Returns a newly
+ * created file descriptor or an error code.
+ */
+int anon_inode_getfd_secure(const char *name, const struct file_operations *fops,
+ void *priv, int flags,
+ const struct inode *context_inode)
+{
+ return _anon_inode_getfd(name, fops, priv, flags,
+ context_inode, true);
+}
+EXPORT_SYMBOL_GPL(anon_inode_getfd_secure);
+
+/**
+ * anon_inode_getfd - creates a new file instance by hooking it up to
+ * an anonymous inode and a dentry that describe
+ * the "class" of the file
+ *
+ * @name: [in] name of the "class" of the new file
+ * @fops: [in] file operations for the new file
+ * @priv: [in] private data for the new file (will be file's private_data)
+ * @flags: [in] flags
+ *
+ * Creates a new file by hooking it on a single inode. This is
+ * useful for files that do not need to have a full-fledged inode in
+ * order to operate correctly. All the files created with
+ * anon_inode_getfile() will use the same singleton inode, reducing
+ * memory use and avoiding code duplication for the file/inode/dentry
+ * setup. Returns a newly created file descriptor or an error code.
+ */
+int anon_inode_getfd(const char *name, const struct file_operations *fops,
+ void *priv, int flags)
+{
+ return _anon_inode_getfd(name, fops, priv, flags, NULL, false);
+}
EXPORT_SYMBOL_GPL(anon_inode_getfd);
static int __init anon_inode_init(void)
@@ -162,4 +274,3 @@ static int __init anon_inode_init(void)
}
fs_initcall(anon_inode_init);
-
@@ -10,12 +10,25 @@
#define _LINUX_ANON_INODES_H
struct file_operations;
+struct inode;
+
+struct file *anon_inode_getfile_secure(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags,
+ const struct inode *context_inode);
struct file *anon_inode_getfile(const char *name,
const struct file_operations *fops,
void *priv, int flags);
+
+int anon_inode_getfd_secure(const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags,
+ const struct inode *context_inode);
+
int anon_inode_getfd(const char *name, const struct file_operations *fops,
void *priv, int flags);
+
#endif /* _LINUX_ANON_INODES_H */
@@ -113,6 +113,8 @@ LSM_HOOK(void, LSM_RET_VOID, inode_free_security, struct inode *inode)
LSM_HOOK(int, 0, inode_init_security, struct inode *inode,
struct inode *dir, const struct qstr *qstr, const char **name,
void **value, size_t *len)
+LSM_HOOK(int, 0, inode_init_security_anon, struct inode *inode,
+ const struct qstr *name, const struct inode *context_inode)
LSM_HOOK(int, 0, inode_create, struct inode *dir, struct dentry *dentry,
umode_t mode)
LSM_HOOK(int, 0, inode_link, struct dentry *old_dentry, struct inode *dir,
@@ -233,6 +233,13 @@
* Returns 0 if @name and @value have been successfully set,
* -EOPNOTSUPP if no security attribute is needed, or
* -ENOMEM on memory allocation failure.
+ * @inode_init_security_anon:
+ * Set up a secure anonymous inode.
+ * @inode contains the inode structure
+ * @name name of the anonymous inode class
+ * @context_inode optional related inode
+ * Returns 0 on success, -EACCESS if the security module denies the
+ * creation of this inode, or another -errno upon other errors.
* @inode_create:
* Check permission to create a regular file.
* @dir contains inode structure of the parent of the new file.
@@ -322,6 +322,9 @@ void security_inode_free(struct inode *inode);
int security_inode_init_security(struct inode *inode, struct inode *dir,
const struct qstr *qstr,
initxattrs initxattrs, void *fs_data);
+int security_inode_init_security_anon(struct inode *inode,
+ const struct qstr *name,
+ const struct inode *context_inode);
int security_old_inode_init_security(struct inode *inode, struct inode *dir,
const struct qstr *qstr, const char **name,
void **value, size_t *len);
@@ -1057,6 +1057,15 @@ int security_inode_init_security(struct inode *inode, struct inode *dir,
}
EXPORT_SYMBOL(security_inode_init_security);
+int
+security_inode_init_security_anon(struct inode *inode,
+ const struct qstr *name,
+ const struct inode *context_inode)
+{
+ return call_int_hook(inode_init_security_anon, 0, inode, name,
+ context_inode);
+}
+
int security_old_inode_init_security(struct inode *inode, struct inode *dir,
const struct qstr *qstr, const char **name,
void **value, size_t *len)