[net-next-2.6.git] / security / tomoyo / mount.c

/*
 * security/tomoyo/mount.c
 *
 * Copyright (C) 2005-2010  NTT DATA CORPORATION
 */

#include <linux/slab.h>
#include "common.h"

/* Keywords for mount restrictions. */

/* Allow to call 'mount --bind /source_dir /dest_dir' */
#define TOMOYO_MOUNT_BIND_KEYWORD                        "--bind"
/* Allow to call 'mount --move /old_dir    /new_dir ' */
#define TOMOYO_MOUNT_MOVE_KEYWORD                        "--move"
/* Allow to call 'mount -o remount /dir             ' */
#define TOMOYO_MOUNT_REMOUNT_KEYWORD                     "--remount"
/* Allow to call 'mount --make-unbindable /dir'       */
#define TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD             "--make-unbindable"
/* Allow to call 'mount --make-private /dir'          */
#define TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD                "--make-private"
/* Allow to call 'mount --make-slave /dir'            */
#define TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD                  "--make-slave"
/* Allow to call 'mount --make-shared /dir'           */
#define TOMOYO_MOUNT_MAKE_SHARED_KEYWORD                 "--make-shared"

/**
 * tomoyo_audit_mount_log - Audit mount log.
 *
 * @r: Pointer to "struct tomoyo_request_info".
 *
 * Returns 0 on success, negative value otherwise.
 */
static int tomoyo_audit_mount_log(struct tomoyo_request_info *r)
{
	const char *dev = r->param.mount.dev->name;
	const char *dir = r->param.mount.dir->name;
	const char *type = r->param.mount.type->name;
	const unsigned long flags = r->param.mount.flags;
	if (r->granted)
		return 0;
	if (!strcmp(type, TOMOYO_MOUNT_REMOUNT_KEYWORD))
		tomoyo_warn_log(r, "mount -o remount %s 0x%lX", dir, flags);
	else if (!strcmp(type, TOMOYO_MOUNT_BIND_KEYWORD)
		 || !strcmp(type, TOMOYO_MOUNT_MOVE_KEYWORD))
		tomoyo_warn_log(r, "mount %s %s %s 0x%lX", type, dev, dir,
				flags);
	else if (!strcmp(type, TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD) ||
		 !strcmp(type, TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD) ||
		 !strcmp(type, TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD) ||
		 !strcmp(type, TOMOYO_MOUNT_MAKE_SHARED_KEYWORD))
		tomoyo_warn_log(r, "mount %s %s 0x%lX", type, dir, flags);
	else
		tomoyo_warn_log(r, "mount -t %s %s %s 0x%lX", type, dev, dir,
				flags);
	return tomoyo_supervisor(r,
				 TOMOYO_KEYWORD_ALLOW_MOUNT "%s %s %s 0x%lX\n",
				 tomoyo_pattern(r->param.mount.dev),
				 tomoyo_pattern(r->param.mount.dir), type,
				 flags);
}

static bool tomoyo_check_mount_acl(const struct tomoyo_request_info *r,
				   const struct tomoyo_acl_info *ptr)
{
	const struct tomoyo_mount_acl *acl =
		container_of(ptr, typeof(*acl), head);
	return tomoyo_compare_number_union(r->param.mount.flags, &acl->flags) &&
		tomoyo_compare_name_union(r->param.mount.type, &acl->fs_type) &&
		tomoyo_compare_name_union(r->param.mount.dir, &acl->dir_name) &&
		(!r->param.mount.need_dev ||
		 tomoyo_compare_name_union(r->param.mount.dev, &acl->dev_name));
}

/**
 * tomoyo_mount_acl - Check permission for mount() operation.
 *
 * @r:        Pointer to "struct tomoyo_request_info".
 * @dev_name: Name of device file.
 * @dir:      Pointer to "struct path".
 * @type:     Name of filesystem type.
 * @flags:    Mount options.
 *
 * Returns 0 on success, negative value otherwise.
 *
 * Caller holds tomoyo_read_lock().
 */
static int tomoyo_mount_acl(struct tomoyo_request_info *r, char *dev_name,
			    struct path *dir, char *type, unsigned long flags)
{
	struct path path;
	struct file_system_type *fstype = NULL;
	const char *requested_type = NULL;
	const char *requested_dir_name = NULL;
	const char *requested_dev_name = NULL;
	struct tomoyo_path_info rtype;
	struct tomoyo_path_info rdev;
	struct tomoyo_path_info rdir;
	int need_dev = 0;
	int error = -ENOMEM;

	/* Get fstype. */
	requested_type = tomoyo_encode(type);
	if (!requested_type)
		goto out;
	rtype.name = requested_type;
	tomoyo_fill_path_info(&rtype);

	/* Get mount point. */
	requested_dir_name = tomoyo_realpath_from_path(dir);
	if (!requested_dir_name) {
		error = -ENOMEM;
		goto out;
	}
	rdir.name = requested_dir_name;
	tomoyo_fill_path_info(&rdir);

	/* Compare fs name. */
	if (!strcmp(type, TOMOYO_MOUNT_REMOUNT_KEYWORD)) {
		/* dev_name is ignored. */
	} else if (!strcmp(type, TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD) ||
		   !strcmp(type, TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD) ||
		   !strcmp(type, TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD) ||
		   !strcmp(type, TOMOYO_MOUNT_MAKE_SHARED_KEYWORD)) {
		/* dev_name is ignored. */
	} else if (!strcmp(type, TOMOYO_MOUNT_BIND_KEYWORD) ||
		   !strcmp(type, TOMOYO_MOUNT_MOVE_KEYWORD)) {
		need_dev = -1; /* dev_name is a directory */
	} else {
		fstype = get_fs_type(type);
		if (!fstype) {
			error = -ENODEV;
			goto out;
		}
		if (fstype->fs_flags & FS_REQUIRES_DEV)
			/* dev_name is a block device file. */
			need_dev = 1;
	}
	if (need_dev) {
		/* Get mount point or device file. */
		if (kern_path(dev_name, LOOKUP_FOLLOW, &path)) {
			error = -ENOENT;
			goto out;
		}
		requested_dev_name = tomoyo_realpath_from_path(&path);
		if (!requested_dev_name) {
			error = -ENOENT;
			goto out;
		}
	} else {
		/* Map dev_name to "<NULL>" if no dev_name given. */
		if (!dev_name)
			dev_name = "<NULL>";
		requested_dev_name = tomoyo_encode(dev_name);
		if (!requested_dev_name) {
			error = -ENOMEM;
			goto out;
		}
	}
	rdev.name = requested_dev_name;
	tomoyo_fill_path_info(&rdev);
	r->param_type = TOMOYO_TYPE_MOUNT_ACL;
	r->param.mount.need_dev = need_dev;
	r->param.mount.dev = &rdev;
	r->param.mount.dir = &rdir;
	r->param.mount.type = &rtype;
	r->param.mount.flags = flags;
	do {
		tomoyo_check_acl(r, tomoyo_check_mount_acl);
		error = tomoyo_audit_mount_log(r);
	} while (error == TOMOYO_RETRY_REQUEST);
 out:
	kfree(requested_dev_name);
	kfree(requested_dir_name);
	if (fstype)
		put_filesystem(fstype);
	kfree(requested_type);
	return error;
}

/**
 * tomoyo_mount_permission - Check permission for mount() operation.
 *
 * @dev_name:  Name of device file.
 * @path:      Pointer to "struct path".
 * @type:      Name of filesystem type. May be NULL.
 * @flags:     Mount options.
 * @data_page: Optional data. May be NULL.
 *
 * Returns 0 on success, negative value otherwise.
 */
int tomoyo_mount_permission(char *dev_name, struct path *path, char *type,
			    unsigned long flags, void *data_page)
{
	struct tomoyo_request_info r;
	int error;
	int idx;

	if (tomoyo_init_request_info(&r, NULL, TOMOYO_MAC_FILE_MOUNT)
	    == TOMOYO_CONFIG_DISABLED)
		return 0;
	if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
		flags &= ~MS_MGC_MSK;
	if (flags & MS_REMOUNT) {
		type = TOMOYO_MOUNT_REMOUNT_KEYWORD;
		flags &= ~MS_REMOUNT;
	}
	if (flags & MS_MOVE) {
		type = TOMOYO_MOUNT_MOVE_KEYWORD;
		flags &= ~MS_MOVE;
	}
	if (flags & MS_BIND) {
		type = TOMOYO_MOUNT_BIND_KEYWORD;
		flags &= ~MS_BIND;
	}
	if (flags & MS_UNBINDABLE) {
		type = TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD;
		flags &= ~MS_UNBINDABLE;
	}
	if (flags & MS_PRIVATE) {
		type = TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD;
		flags &= ~MS_PRIVATE;
	}
	if (flags & MS_SLAVE) {
		type = TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD;
		flags &= ~MS_SLAVE;
	}
	if (flags & MS_SHARED) {
		type = TOMOYO_MOUNT_MAKE_SHARED_KEYWORD;
		flags &= ~MS_SHARED;
	}
	if (!type)
		type = "<NULL>";
	idx = tomoyo_read_lock();
	error = tomoyo_mount_acl(&r, dev_name, path, type, flags);
	tomoyo_read_unlock(idx);
	return error;
}

static bool tomoyo_same_mount_acl(const struct tomoyo_acl_info *a,
				  const struct tomoyo_acl_info *b)
{
	const struct tomoyo_mount_acl *p1 = container_of(a, typeof(*p1), head);
	const struct tomoyo_mount_acl *p2 = container_of(b, typeof(*p2), head);
	return tomoyo_same_acl_head(&p1->head, &p2->head) &&
		tomoyo_same_name_union(&p1->dev_name, &p2->dev_name) &&
		tomoyo_same_name_union(&p1->dir_name, &p2->dir_name) &&
		tomoyo_same_name_union(&p1->fs_type, &p2->fs_type) &&
		tomoyo_same_number_union(&p1->flags, &p2->flags);
}

/**
 * tomoyo_write_mount - Write "struct tomoyo_mount_acl" list.
 *
 * @data:      String to parse.
 * @domain:    Pointer to "struct tomoyo_domain_info".
 * @is_delete: True if it is a delete request.
 *
 * Returns 0 on success, negative value otherwise.
 *
 * Caller holds tomoyo_read_lock().
 */
int tomoyo_write_mount(char *data, struct tomoyo_domain_info *domain,
		       const bool is_delete)
{
	struct tomoyo_mount_acl e = { .head.type = TOMOYO_TYPE_MOUNT_ACL };
	int error = is_delete ? -ENOENT : -ENOMEM;
	char *w[4];
	if (!tomoyo_tokenize(data, w, sizeof(w)) || !w[3][0])
		return -EINVAL;
	if (!tomoyo_parse_name_union(w[0], &e.dev_name) ||
	    !tomoyo_parse_name_union(w[1], &e.dir_name) ||
	    !tomoyo_parse_name_union(w[2], &e.fs_type) ||
	    !tomoyo_parse_number_union(w[3], &e.flags))
		goto out;
	error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
				     tomoyo_same_mount_acl, NULL);
 out:
	tomoyo_put_name_union(&e.dev_name);
	tomoyo_put_name_union(&e.dir_name);
	tomoyo_put_name_union(&e.fs_type);
	tomoyo_put_number_union(&e.flags);
	return error;
}
Commit	Line	Data
2106ccd9 TH	1	/*
	2	* security/tomoyo/mount.c
	3	*
	4	* Copyright (C) 2005-2010 NTT DATA CORPORATION
	5	*/
	6
	7	#include <linux/slab.h>
	8	#include "common.h"
	9
	10	/* Keywords for mount restrictions. */
	11
	12	/* Allow to call 'mount --bind /source_dir /dest_dir' */
	13	#define TOMOYO_MOUNT_BIND_KEYWORD "--bind"
	14	/* Allow to call 'mount --move /old_dir /new_dir ' */
	15	#define TOMOYO_MOUNT_MOVE_KEYWORD "--move"
	16	/* Allow to call 'mount -o remount /dir ' */
	17	#define TOMOYO_MOUNT_REMOUNT_KEYWORD "--remount"
	18	/* Allow to call 'mount --make-unbindable /dir' */
	19	#define TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD "--make-unbindable"
	20	/* Allow to call 'mount --make-private /dir' */
	21	#define TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD "--make-private"
	22	/* Allow to call 'mount --make-slave /dir' */
	23	#define TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD "--make-slave"
	24	/* Allow to call 'mount --make-shared /dir' */
	25	#define TOMOYO_MOUNT_MAKE_SHARED_KEYWORD "--make-shared"
	26
99a85259 TH	27	/**
	28	* tomoyo_audit_mount_log - Audit mount log.
	29	*
	30	* @r: Pointer to "struct tomoyo_request_info".
	31	*
	32	* Returns 0 on success, negative value otherwise.
	33	*/
	34	static int tomoyo_audit_mount_log(struct tomoyo_request_info *r)
	35	{
	36	const char *dev = r->param.mount.dev->name;
	37	const char *dir = r->param.mount.dir->name;
	38	const char *type = r->param.mount.type->name;
	39	const unsigned long flags = r->param.mount.flags;
	40	if (r->granted)
	41	return 0;
	42	if (!strcmp(type, TOMOYO_MOUNT_REMOUNT_KEYWORD))
	43	tomoyo_warn_log(r, "mount -o remount %s 0x%lX", dir, flags);
	44	else if (!strcmp(type, TOMOYO_MOUNT_BIND_KEYWORD)
	45	\|\| !strcmp(type, TOMOYO_MOUNT_MOVE_KEYWORD))
	46	tomoyo_warn_log(r, "mount %s %s %s 0x%lX", type, dev, dir,
	47	flags);
	48	else if (!strcmp(type, TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD) \|\|
	49	!strcmp(type, TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD) \|\|
	50	!strcmp(type, TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD) \|\|
	51	!strcmp(type, TOMOYO_MOUNT_MAKE_SHARED_KEYWORD))
	52	tomoyo_warn_log(r, "mount %s %s 0x%lX", type, dir, flags);
	53	else
	54	tomoyo_warn_log(r, "mount -t %s %s %s 0x%lX", type, dev, dir,
	55	flags);
	56	return tomoyo_supervisor(r,
	57	TOMOYO_KEYWORD_ALLOW_MOUNT "%s %s %s 0x%lX\n",
e2bf6907 TH	58	tomoyo_pattern(r->param.mount.dev),
e2bf6907 TH	59	tomoyo_pattern(r->param.mount.dir), type,
99a85259 TH	60	flags);
	61	}
	62
	63	static bool tomoyo_check_mount_acl(const struct tomoyo_request_info *r,
	64	const struct tomoyo_acl_info *ptr)
	65	{
	66	const struct tomoyo_mount_acl *acl =
	67	container_of(ptr, typeof(*acl), head);
	68	return tomoyo_compare_number_union(r->param.mount.flags, &acl->flags) &&
	69	tomoyo_compare_name_union(r->param.mount.type, &acl->fs_type) &&
	70	tomoyo_compare_name_union(r->param.mount.dir, &acl->dir_name) &&
	71	(!r->param.mount.need_dev \|\|
	72	tomoyo_compare_name_union(r->param.mount.dev, &acl->dev_name));
	73	}
	74
2106ccd9	75	/**
d795ef9e	76	* tomoyo_mount_acl - Check permission for mount() operation.
2106ccd9 TH	77	*
	78	* @r: Pointer to "struct tomoyo_request_info".
	79	* @dev_name: Name of device file.
	80	* @dir: Pointer to "struct path".
	81	* @type: Name of filesystem type.
	82	* @flags: Mount options.
	83	*
	84	* Returns 0 on success, negative value otherwise.
	85	*
	86	* Caller holds tomoyo_read_lock().
	87	*/
d795ef9e TH	88	static int tomoyo_mount_acl(struct tomoyo_request_info r, char dev_name,
d795ef9e TH	89	struct path dir, char type, unsigned long flags)
2106ccd9 TH	90	{
2106ccd9 TH	91	struct path path;
2106ccd9 TH	92	struct file_system_type *fstype = NULL;
	93	const char *requested_type = NULL;
	94	const char *requested_dir_name = NULL;
	95	const char *requested_dev_name = NULL;
	96	struct tomoyo_path_info rtype;
	97	struct tomoyo_path_info rdev;
	98	struct tomoyo_path_info rdir;
	99	int need_dev = 0;
	100	int error = -ENOMEM;
	101
	102	/* Get fstype. */
c8c57e84	103	requested_type = tomoyo_encode(type);
2106ccd9 TH	104	if (!requested_type)
	105	goto out;
	106	rtype.name = requested_type;
	107	tomoyo_fill_path_info(&rtype);
	108
	109	/* Get mount point. */
	110	requested_dir_name = tomoyo_realpath_from_path(dir);
	111	if (!requested_dir_name) {
	112	error = -ENOMEM;
	113	goto out;
	114	}
	115	rdir.name = requested_dir_name;
	116	tomoyo_fill_path_info(&rdir);
	117
	118	/* Compare fs name. */
	119	if (!strcmp(type, TOMOYO_MOUNT_REMOUNT_KEYWORD)) {
	120	/* dev_name is ignored. */
	121	} else if (!strcmp(type, TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD) \|\|
	122	!strcmp(type, TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD) \|\|
	123	!strcmp(type, TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD) \|\|
	124	!strcmp(type, TOMOYO_MOUNT_MAKE_SHARED_KEYWORD)) {
	125	/* dev_name is ignored. */
	126	} else if (!strcmp(type, TOMOYO_MOUNT_BIND_KEYWORD) \|\|
	127	!strcmp(type, TOMOYO_MOUNT_MOVE_KEYWORD)) {
	128	need_dev = -1; /* dev_name is a directory */
	129	} else {
	130	fstype = get_fs_type(type);
	131	if (!fstype) {
	132	error = -ENODEV;
	133	goto out;
	134	}
	135	if (fstype->fs_flags & FS_REQUIRES_DEV)
	136	/* dev_name is a block device file. */
	137	need_dev = 1;
	138	}
	139	if (need_dev) {
	140	/* Get mount point or device file. */
	141	if (kern_path(dev_name, LOOKUP_FOLLOW, &path)) {
	142	error = -ENOENT;
	143	goto out;
	144	}
	145	requested_dev_name = tomoyo_realpath_from_path(&path);
	146	if (!requested_dev_name) {
	147	error = -ENOENT;
	148	goto out;
	149	}
	150	} else {
	151	/* Map dev_name to "<NULL>" if no dev_name given. */
	152	if (!dev_name)
	153	dev_name = "<NULL>";
c8c57e84	154	requested_dev_name = tomoyo_encode(dev_name);
2106ccd9 TH	155	if (!requested_dev_name) {
	156	error = -ENOMEM;
	157	goto out;
	158	}
	159	}
	160	rdev.name = requested_dev_name;
	161	tomoyo_fill_path_info(&rdev);
cf6e9a64 TH	162	r->param_type = TOMOYO_TYPE_MOUNT_ACL;
	163	r->param.mount.need_dev = need_dev;
	164	r->param.mount.dev = &rdev;
	165	r->param.mount.dir = &rdir;
	166	r->param.mount.type = &rtype;
	167	r->param.mount.flags = flags;
99a85259 TH	168	do {
	169	tomoyo_check_acl(r, tomoyo_check_mount_acl);
	170	error = tomoyo_audit_mount_log(r);
	171	} while (error == TOMOYO_RETRY_REQUEST);
2106ccd9 TH	172	out:
	173	kfree(requested_dev_name);
	174	kfree(requested_dir_name);
	175	if (fstype)
	176	put_filesystem(fstype);
	177	kfree(requested_type);
	178	return error;
	179	}
	180
2106ccd9 TH	181	/**
	182	* tomoyo_mount_permission - Check permission for mount() operation.
	183	*
	184	* @dev_name: Name of device file.
	185	* @path: Pointer to "struct path".
	186	* @type: Name of filesystem type. May be NULL.
	187	* @flags: Mount options.
	188	* @data_page: Optional data. May be NULL.
	189	*
	190	* Returns 0 on success, negative value otherwise.
	191	*/
	192	int tomoyo_mount_permission(char dev_name, struct path path, char *type,
	193	unsigned long flags, void *data_page)
	194	{
	195	struct tomoyo_request_info r;
	196	int error;
	197	int idx;
	198
57c2590f TH	199	if (tomoyo_init_request_info(&r, NULL, TOMOYO_MAC_FILE_MOUNT)
57c2590f TH	200	== TOMOYO_CONFIG_DISABLED)
2106ccd9	201	return 0;
d795ef9e TH	202	if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
	203	flags &= ~MS_MGC_MSK;
	204	if (flags & MS_REMOUNT) {
	205	type = TOMOYO_MOUNT_REMOUNT_KEYWORD;
	206	flags &= ~MS_REMOUNT;
	207	}
	208	if (flags & MS_MOVE) {
	209	type = TOMOYO_MOUNT_MOVE_KEYWORD;
	210	flags &= ~MS_MOVE;
	211	}
	212	if (flags & MS_BIND) {
	213	type = TOMOYO_MOUNT_BIND_KEYWORD;
	214	flags &= ~MS_BIND;
	215	}
	216	if (flags & MS_UNBINDABLE) {
	217	type = TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD;
	218	flags &= ~MS_UNBINDABLE;
	219	}
	220	if (flags & MS_PRIVATE) {
	221	type = TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD;
	222	flags &= ~MS_PRIVATE;
	223	}
	224	if (flags & MS_SLAVE) {
	225	type = TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD;
	226	flags &= ~MS_SLAVE;
	227	}
	228	if (flags & MS_SHARED) {
	229	type = TOMOYO_MOUNT_MAKE_SHARED_KEYWORD;
	230	flags &= ~MS_SHARED;
	231	}
2106ccd9 TH	232	if (!type)
	233	type = "<NULL>";
	234	idx = tomoyo_read_lock();
	235	error = tomoyo_mount_acl(&r, dev_name, path, type, flags);
	236	tomoyo_read_unlock(idx);
	237	return error;
	238	}
	239
237ab459 TH	240	static bool tomoyo_same_mount_acl(const struct tomoyo_acl_info *a,
	241	const struct tomoyo_acl_info *b)
	242	{
	243	const struct tomoyo_mount_acl p1 = container_of(a, typeof(p1), head);
	244	const struct tomoyo_mount_acl p2 = container_of(b, typeof(p2), head);
75093152 TH	245	return tomoyo_same_acl_head(&p1->head, &p2->head) &&
	246	tomoyo_same_name_union(&p1->dev_name, &p2->dev_name) &&
	247	tomoyo_same_name_union(&p1->dir_name, &p2->dir_name) &&
	248	tomoyo_same_name_union(&p1->fs_type, &p2->fs_type) &&
	249	tomoyo_same_number_union(&p1->flags, &p2->flags);
237ab459 TH	250	}
237ab459 TH	251
2106ccd9	252	/**
e2bf6907	253	* tomoyo_write_mount - Write "struct tomoyo_mount_acl" list.
2106ccd9 TH	254	*
	255	* @data: String to parse.
	256	* @domain: Pointer to "struct tomoyo_domain_info".
	257	* @is_delete: True if it is a delete request.
	258	*
	259	* Returns 0 on success, negative value otherwise.
237ab459 TH	260	*
237ab459 TH	261	* Caller holds tomoyo_read_lock().
2106ccd9	262	*/
e2bf6907 TH	263	int tomoyo_write_mount(char data, struct tomoyo_domain_info domain,
e2bf6907 TH	264	const bool is_delete)
2106ccd9	265	{
2106ccd9 TH	266	struct tomoyo_mount_acl e = { .head.type = TOMOYO_TYPE_MOUNT_ACL };
	267	int error = is_delete ? -ENOENT : -ENOMEM;
	268	char *w[4];
	269	if (!tomoyo_tokenize(data, w, sizeof(w)) \|\| !w[3][0])
	270	return -EINVAL;
	271	if (!tomoyo_parse_name_union(w[0], &e.dev_name) \|\|
	272	!tomoyo_parse_name_union(w[1], &e.dir_name) \|\|
	273	!tomoyo_parse_name_union(w[2], &e.fs_type) \|\|
	274	!tomoyo_parse_number_union(w[3], &e.flags))
	275	goto out;
237ab459 TH	276	error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
237ab459 TH	277	tomoyo_same_mount_acl, NULL);
2106ccd9 TH	278	out:
	279	tomoyo_put_name_union(&e.dev_name);
	280	tomoyo_put_name_union(&e.dir_name);
	281	tomoyo_put_name_union(&e.fs_type);
	282	tomoyo_put_number_union(&e.flags);
	283	return error;
	284	}