[linux.git] / fs / ntfs3 / attrlist.c

// SPDX-License-Identifier: GPL-2.0
/*
 *
 * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
 *
 */

#include <linux/fs.h>

#include "debug.h"
#include "ntfs.h"
#include "ntfs_fs.h"

/*
 * al_is_valid_le
 *
 * Return: True if @le is valid.
 */
static inline bool al_is_valid_le(const struct ntfs_inode *ni,
				  struct ATTR_LIST_ENTRY *le)
{
	if (!le || !ni->attr_list.le || !ni->attr_list.size)
		return false;

	return PtrOffset(ni->attr_list.le, le) + le16_to_cpu(le->size) <=
	       ni->attr_list.size;
}

void al_destroy(struct ntfs_inode *ni)
{
	run_close(&ni->attr_list.run);
	kfree(ni->attr_list.le);
	ni->attr_list.le = NULL;
	ni->attr_list.size = 0;
	ni->attr_list.dirty = false;
}

/*
 * ntfs_load_attr_list
 *
 * This method makes sure that the ATTRIB list, if present,
 * has been properly set up.
 */
int ntfs_load_attr_list(struct ntfs_inode *ni, struct ATTRIB *attr)
{
	int err;
	size_t lsize;
	void *le = NULL;

	if (ni->attr_list.size)
		return 0;

	if (!attr->non_res) {
		lsize = le32_to_cpu(attr->res.data_size);
		le = kmalloc(al_aligned(lsize), GFP_NOFS);
		if (!le) {
			err = -ENOMEM;
			goto out;
		}
		memcpy(le, resident_data(attr), lsize);
	} else if (attr->nres.svcn) {
		err = -EINVAL;
		goto out;
	} else {
		u16 run_off = le16_to_cpu(attr->nres.run_off);

		lsize = le64_to_cpu(attr->nres.data_size);

		run_init(&ni->attr_list.run);

		if (run_off > le32_to_cpu(attr->size)) {
			err = -EINVAL;
			goto out;
		}

		err = run_unpack_ex(&ni->attr_list.run, ni->mi.sbi, ni->mi.rno,
				    0, le64_to_cpu(attr->nres.evcn), 0,
				    Add2Ptr(attr, run_off),
				    le32_to_cpu(attr->size) - run_off);
		if (err < 0)
			goto out;

		le = kmalloc(al_aligned(lsize), GFP_NOFS);
		if (!le) {
			err = -ENOMEM;
			goto out;
		}

		err = ntfs_read_run_nb(ni->mi.sbi, &ni->attr_list.run, 0, le,
				       lsize, NULL);
		if (err)
			goto out;
	}

	ni->attr_list.size = lsize;
	ni->attr_list.le = le;

	return 0;

out:
	ni->attr_list.le = le;
	al_destroy(ni);

	return err;
}

/*
 * al_enumerate
 *
 * Return:
 * * The next list le.
 * * If @le is NULL then return the first le.
 */
struct ATTR_LIST_ENTRY *al_enumerate(struct ntfs_inode *ni,
				     struct ATTR_LIST_ENTRY *le)
{
	size_t off;
	u16 sz;

	if (!le) {
		le = ni->attr_list.le;
	} else {
		sz = le16_to_cpu(le->size);
		if (sz < sizeof(struct ATTR_LIST_ENTRY)) {
			/* Impossible 'cause we should not return such le. */
			return NULL;
		}
		le = Add2Ptr(le, sz);
	}

	/* Check boundary. */
	off = PtrOffset(ni->attr_list.le, le);
	if (off + sizeof(struct ATTR_LIST_ENTRY) > ni->attr_list.size) {
		/* The regular end of list. */
		return NULL;
	}

	sz = le16_to_cpu(le->size);

	/* Check le for errors. */
	if (sz < sizeof(struct ATTR_LIST_ENTRY) ||
	    off + sz > ni->attr_list.size ||
	    sz < le->name_off + le->name_len * sizeof(short)) {
		return NULL;
	}

	return le;
}

/*
 * al_find_le
 *
 * Find the first le in the list which matches type, name and VCN.
 *
 * Return: NULL if not found.
 */
struct ATTR_LIST_ENTRY *al_find_le(struct ntfs_inode *ni,
				   struct ATTR_LIST_ENTRY *le,
				   const struct ATTRIB *attr)
{
	CLST svcn = attr_svcn(attr);

	return al_find_ex(ni, le, attr->type, attr_name(attr), attr->name_len,
			  &svcn);
}

/*
 * al_find_ex
 *
 * Find the first le in the list which matches type, name and VCN.
 *
 * Return: NULL if not found.
 */
struct ATTR_LIST_ENTRY *al_find_ex(struct ntfs_inode *ni,
				   struct ATTR_LIST_ENTRY *le,
				   enum ATTR_TYPE type, const __le16 *name,
				   u8 name_len, const CLST *vcn)
{
	struct ATTR_LIST_ENTRY *ret = NULL;
	u32 type_in = le32_to_cpu(type);

	while ((le = al_enumerate(ni, le))) {
		u64 le_vcn;
		int diff = le32_to_cpu(le->type) - type_in;

		/* List entries are sorted by type, name and VCN. */
		if (diff < 0)
			continue;

		if (diff > 0)
			return ret;

		if (le->name_len != name_len)
			continue;

		le_vcn = le64_to_cpu(le->vcn);
		if (!le_vcn) {
			/*
			 * Compare entry names only for entry with vcn == 0.
			 */
			diff = ntfs_cmp_names(le_name(le), name_len, name,
					      name_len, ni->mi.sbi->upcase,
					      true);
			if (diff < 0)
				continue;

			if (diff > 0)
				return ret;
		}

		if (!vcn)
			return le;

		if (*vcn == le_vcn)
			return le;

		if (*vcn < le_vcn)
			return ret;

		ret = le;
	}

	return ret;
}

/*
 * al_find_le_to_insert
 *
 * Find the first list entry which matches type, name and VCN.
 */
static struct ATTR_LIST_ENTRY *al_find_le_to_insert(struct ntfs_inode *ni,
						    enum ATTR_TYPE type,
						    const __le16 *name,
						    u8 name_len, CLST vcn)
{
	struct ATTR_LIST_ENTRY *le = NULL, *prev;
	u32 type_in = le32_to_cpu(type);

	/* List entries are sorted by type, name and VCN. */
	while ((le = al_enumerate(ni, prev = le))) {
		int diff = le32_to_cpu(le->type) - type_in;

		if (diff < 0)
			continue;

		if (diff > 0)
			return le;

		if (!le->vcn) {
			/*
			 * Compare entry names only for entry with vcn == 0.
			 */
			diff = ntfs_cmp_names(le_name(le), le->name_len, name,
					      name_len, ni->mi.sbi->upcase,
					      true);
			if (diff < 0)
				continue;

			if (diff > 0)
				return le;
		}

		if (le64_to_cpu(le->vcn) >= vcn)
			return le;
	}

	return prev ? Add2Ptr(prev, le16_to_cpu(prev->size)) : ni->attr_list.le;
}

/*
 * al_add_le
 *
 * Add an "attribute list entry" to the list.
 */
int al_add_le(struct ntfs_inode *ni, enum ATTR_TYPE type, const __le16 *name,
	      u8 name_len, CLST svcn, __le16 id, const struct MFT_REF *ref,
	      struct ATTR_LIST_ENTRY **new_le)
{
	int err;
	struct ATTRIB *attr;
	struct ATTR_LIST_ENTRY *le;
	size_t off;
	u16 sz;
	size_t asize, new_asize, old_size;
	u64 new_size;
	typeof(ni->attr_list) *al = &ni->attr_list;

	/*
	 * Compute the size of the new 'le'
	 */
	sz = le_size(name_len);
	old_size = al->size;
	new_size = old_size + sz;
	asize = al_aligned(old_size);
	new_asize = al_aligned(new_size);

	/* Scan forward to the point at which the new 'le' should be inserted. */
	le = al_find_le_to_insert(ni, type, name, name_len, svcn);
	off = PtrOffset(al->le, le);

	if (new_size > asize) {
		void *ptr = kmalloc(new_asize, GFP_NOFS);

		if (!ptr)
			return -ENOMEM;

		memcpy(ptr, al->le, off);
		memcpy(Add2Ptr(ptr, off + sz), le, old_size - off);
		le = Add2Ptr(ptr, off);
		kfree(al->le);
		al->le = ptr;
	} else {
		memmove(Add2Ptr(le, sz), le, old_size - off);
	}
	*new_le = le;

	al->size = new_size;

	le->type = type;
	le->size = cpu_to_le16(sz);
	le->name_len = name_len;
	le->name_off = offsetof(struct ATTR_LIST_ENTRY, name);
	le->vcn = cpu_to_le64(svcn);
	le->ref = *ref;
	le->id = id;
	memcpy(le->name, name, sizeof(short) * name_len);

	err = attr_set_size(ni, ATTR_LIST, NULL, 0, &al->run, new_size,
			    &new_size, true, &attr);
	if (err) {
		/* Undo memmove above. */
		memmove(le, Add2Ptr(le, sz), old_size - off);
		al->size = old_size;
		return err;
	}

	al->dirty = true;

	if (attr && attr->non_res) {
		err = ntfs_sb_write_run(ni->mi.sbi, &al->run, 0, al->le,
					al->size, 0);
		if (err)
			return err;
		al->dirty = false;
	}

	return 0;
}

/*
 * al_remove_le - Remove @le from attribute list.
 */
bool al_remove_le(struct ntfs_inode *ni, struct ATTR_LIST_ENTRY *le)
{
	u16 size;
	size_t off;
	typeof(ni->attr_list) *al = &ni->attr_list;

	if (!al_is_valid_le(ni, le))
		return false;

	/* Save on stack the size of 'le' */
	size = le16_to_cpu(le->size);
	off = PtrOffset(al->le, le);

	memmove(le, Add2Ptr(le, size), al->size - (off + size));

	al->size -= size;
	al->dirty = true;

	return true;
}

/*
 * al_delete_le - Delete first le from the list which matches its parameters.
 */
bool al_delete_le(struct ntfs_inode *ni, enum ATTR_TYPE type, CLST vcn,
		  const __le16 *name, size_t name_len,
		  const struct MFT_REF *ref)
{
	u16 size;
	struct ATTR_LIST_ENTRY *le;
	size_t off;
	typeof(ni->attr_list) *al = &ni->attr_list;

	/* Scan forward to the first le that matches the input. */
	le = al_find_ex(ni, NULL, type, name, name_len, &vcn);
	if (!le)
		return false;

	off = PtrOffset(al->le, le);

next:
	if (off >= al->size)
		return false;
	if (le->type != type)
		return false;
	if (le->name_len != name_len)
		return false;
	if (name_len && ntfs_cmp_names(le_name(le), name_len, name, name_len,
				       ni->mi.sbi->upcase, true))
		return false;
	if (le64_to_cpu(le->vcn) != vcn)
		return false;

	/*
	 * The caller specified a segment reference, so we have to
	 * scan through the matching entries until we find that segment
	 * reference or we run of matching entries.
	 */
	if (ref && memcmp(ref, &le->ref, sizeof(*ref))) {
		off += le16_to_cpu(le->size);
		le = Add2Ptr(al->le, off);
		goto next;
	}

	/* Save on stack the size of 'le'. */
	size = le16_to_cpu(le->size);
	/* Delete the le. */
	memmove(le, Add2Ptr(le, size), al->size - (off + size));

	al->size -= size;
	al->dirty = true;

	return true;
}

int al_update(struct ntfs_inode *ni, int sync)
{
	int err;
	struct ATTRIB *attr;
	typeof(ni->attr_list) *al = &ni->attr_list;

	if (!al->dirty || !al->size)
		return 0;

	/*
	 * Attribute list increased on demand in al_add_le.
	 * Attribute list decreased here.
	 */
	err = attr_set_size(ni, ATTR_LIST, NULL, 0, &al->run, al->size, NULL,
			    false, &attr);
	if (err)
		goto out;

	if (!attr->non_res) {
		memcpy(resident_data(attr), al->le, al->size);
	} else {
		err = ntfs_sb_write_run(ni->mi.sbi, &al->run, 0, al->le,
					al->size, sync);
		if (err)
			goto out;

		attr->nres.valid_size = attr->nres.data_size;
	}

	ni->mi.dirty = true;
	al->dirty = false;

out:
	return err;
}
Commit	Line	Data
be71b5cb KK	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	*
	4	* Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
	5	*
	6	*/
	7
be71b5cb	8	#include <linux/fs.h>
be71b5cb KK	9
	10	#include "debug.h"
	11	#include "ntfs.h"
	12	#include "ntfs_fs.h"
	13
e8b8e97f KA	14	/*
	15	* al_is_valid_le
	16	*
	17	* Return: True if @le is valid.
	18	*/
be71b5cb KK	19	static inline bool al_is_valid_le(const struct ntfs_inode *ni,
	20	struct ATTR_LIST_ENTRY *le)
	21	{
	22	if (!le \|\| !ni->attr_list.le \|\| !ni->attr_list.size)
	23	return false;
	24
	25	return PtrOffset(ni->attr_list.le, le) + le16_to_cpu(le->size) <=
	26	ni->attr_list.size;
	27	}
	28
	29	void al_destroy(struct ntfs_inode *ni)
	30	{
	31	run_close(&ni->attr_list.run);
195c52bd	32	kfree(ni->attr_list.le);
be71b5cb KK	33	ni->attr_list.le = NULL;
	34	ni->attr_list.size = 0;
	35	ni->attr_list.dirty = false;
	36	}
	37
	38	/*
	39	* ntfs_load_attr_list
	40	*
	41	* This method makes sure that the ATTRIB list, if present,
	42	* has been properly set up.
	43	*/
	44	int ntfs_load_attr_list(struct ntfs_inode ni, struct ATTRIB attr)
	45	{
	46	int err;
	47	size_t lsize;
	48	void *le = NULL;
	49
	50	if (ni->attr_list.size)
	51	return 0;
	52
	53	if (!attr->non_res) {
	54	lsize = le32_to_cpu(attr->res.data_size);
195c52bd	55	le = kmalloc(al_aligned(lsize), GFP_NOFS);
be71b5cb KK	56	if (!le) {
	57	err = -ENOMEM;
	58	goto out;
	59	}
	60	memcpy(le, resident_data(attr), lsize);
	61	} else if (attr->nres.svcn) {
	62	err = -EINVAL;
	63	goto out;
	64	} else {
	65	u16 run_off = le16_to_cpu(attr->nres.run_off);
	66
	67	lsize = le64_to_cpu(attr->nres.data_size);
	68
	69	run_init(&ni->attr_list.run);
	70
6db62086 EL	71	if (run_off > le32_to_cpu(attr->size)) {
	72	err = -EINVAL;
	73	goto out;
	74	}
	75
be71b5cb KK	76	err = run_unpack_ex(&ni->attr_list.run, ni->mi.sbi, ni->mi.rno,
	77	0, le64_to_cpu(attr->nres.evcn), 0,
	78	Add2Ptr(attr, run_off),
	79	le32_to_cpu(attr->size) - run_off);
	80	if (err < 0)
	81	goto out;
	82
195c52bd	83	le = kmalloc(al_aligned(lsize), GFP_NOFS);
be71b5cb KK	84	if (!le) {
	85	err = -ENOMEM;
	86	goto out;
	87	}
	88
	89	err = ntfs_read_run_nb(ni->mi.sbi, &ni->attr_list.run, 0, le,
	90	lsize, NULL);
	91	if (err)
	92	goto out;
	93	}
	94
	95	ni->attr_list.size = lsize;
	96	ni->attr_list.le = le;
	97
	98	return 0;
	99
	100	out:
	101	ni->attr_list.le = le;
	102	al_destroy(ni);
	103
	104	return err;
	105	}
	106
	107	/*
	108	* al_enumerate
	109	*
e8b8e97f KA	110	* Return:
	111	* * The next list le.
	112	* * If @le is NULL then return the first le.
be71b5cb KK	113	*/
	114	struct ATTR_LIST_ENTRY al_enumerate(struct ntfs_inode ni,
	115	struct ATTR_LIST_ENTRY *le)
	116	{
	117	size_t off;
	118	u16 sz;
	119
	120	if (!le) {
	121	le = ni->attr_list.le;
	122	} else {
	123	sz = le16_to_cpu(le->size);
	124	if (sz < sizeof(struct ATTR_LIST_ENTRY)) {
e8b8e97f	125	/* Impossible 'cause we should not return such le. */
be71b5cb KK	126	return NULL;
	127	}
	128	le = Add2Ptr(le, sz);
	129	}
	130
e8b8e97f	131	/* Check boundary. */
be71b5cb KK	132	off = PtrOffset(ni->attr_list.le, le);
be71b5cb KK	133	if (off + sizeof(struct ATTR_LIST_ENTRY) > ni->attr_list.size) {
e8b8e97f	134	/* The regular end of list. */
be71b5cb KK	135	return NULL;
	136	}
	137
	138	sz = le16_to_cpu(le->size);
	139
e8b8e97f	140	/* Check le for errors. */
be71b5cb KK	141	if (sz < sizeof(struct ATTR_LIST_ENTRY) \|\|
	142	off + sz > ni->attr_list.size \|\|
	143	sz < le->name_off + le->name_len * sizeof(short)) {
	144	return NULL;
	145	}
	146
	147	return le;
	148	}
	149
	150	/*
	151	* al_find_le
	152	*
e8b8e97f KA	153	* Find the first le in the list which matches type, name and VCN.
	154	*
	155	* Return: NULL if not found.
be71b5cb KK	156	*/
	157	struct ATTR_LIST_ENTRY al_find_le(struct ntfs_inode ni,
	158	struct ATTR_LIST_ENTRY *le,
	159	const struct ATTRIB *attr)
	160	{
	161	CLST svcn = attr_svcn(attr);
	162
	163	return al_find_ex(ni, le, attr->type, attr_name(attr), attr->name_len,
	164	&svcn);
	165	}
	166
	167	/*
	168	* al_find_ex
	169	*
e8b8e97f KA	170	* Find the first le in the list which matches type, name and VCN.
	171	*
	172	* Return: NULL if not found.
be71b5cb KK	173	*/
	174	struct ATTR_LIST_ENTRY al_find_ex(struct ntfs_inode ni,
	175	struct ATTR_LIST_ENTRY *le,
	176	enum ATTR_TYPE type, const __le16 *name,
	177	u8 name_len, const CLST *vcn)
	178	{
	179	struct ATTR_LIST_ENTRY *ret = NULL;
	180	u32 type_in = le32_to_cpu(type);
	181
	182	while ((le = al_enumerate(ni, le))) {
	183	u64 le_vcn;
	184	int diff = le32_to_cpu(le->type) - type_in;
	185
e8b8e97f	186	/* List entries are sorted by type, name and VCN. */
be71b5cb KK	187	if (diff < 0)
	188	continue;
	189
	190	if (diff > 0)
	191	return ret;
	192
	193	if (le->name_len != name_len)
	194	continue;
	195
	196	le_vcn = le64_to_cpu(le->vcn);
	197	if (!le_vcn) {
	198	/*
e8b8e97f	199	* Compare entry names only for entry with vcn == 0.
be71b5cb KK	200	*/
	201	diff = ntfs_cmp_names(le_name(le), name_len, name,
	202	name_len, ni->mi.sbi->upcase,
	203	true);
	204	if (diff < 0)
	205	continue;
	206
	207	if (diff > 0)
	208	return ret;
	209	}
	210
	211	if (!vcn)
	212	return le;
	213
	214	if (*vcn == le_vcn)
	215	return le;
	216
	217	if (*vcn < le_vcn)
	218	return ret;
	219
	220	ret = le;
	221	}
	222
	223	return ret;
	224	}
	225
	226	/*
	227	* al_find_le_to_insert
	228	*
e8b8e97f	229	* Find the first list entry which matches type, name and VCN.
be71b5cb KK	230	*/
	231	static struct ATTR_LIST_ENTRY al_find_le_to_insert(struct ntfs_inode ni,
	232	enum ATTR_TYPE type,
	233	const __le16 *name,
	234	u8 name_len, CLST vcn)
	235	{
	236	struct ATTR_LIST_ENTRY le = NULL, prev;
	237	u32 type_in = le32_to_cpu(type);
	238
e8b8e97f	239	/* List entries are sorted by type, name and VCN. */
be71b5cb KK	240	while ((le = al_enumerate(ni, prev = le))) {
	241	int diff = le32_to_cpu(le->type) - type_in;
	242
	243	if (diff < 0)
	244	continue;
	245
	246	if (diff > 0)
	247	return le;
	248
	249	if (!le->vcn) {
	250	/*
e8b8e97f	251	* Compare entry names only for entry with vcn == 0.
be71b5cb KK	252	*/
	253	diff = ntfs_cmp_names(le_name(le), le->name_len, name,
	254	name_len, ni->mi.sbi->upcase,
	255	true);
	256	if (diff < 0)
	257	continue;
	258
	259	if (diff > 0)
	260	return le;
	261	}
	262
	263	if (le64_to_cpu(le->vcn) >= vcn)
	264	return le;
	265	}
	266
	267	return prev ? Add2Ptr(prev, le16_to_cpu(prev->size)) : ni->attr_list.le;
	268	}
	269
	270	/*
	271	* al_add_le
	272	*
e8b8e97f	273	* Add an "attribute list entry" to the list.
be71b5cb KK	274	*/
	275	int al_add_le(struct ntfs_inode ni, enum ATTR_TYPE type, const __le16 name,
	276	u8 name_len, CLST svcn, __le16 id, const struct MFT_REF *ref,
	277	struct ATTR_LIST_ENTRY **new_le)
	278	{
	279	int err;
	280	struct ATTRIB *attr;
	281	struct ATTR_LIST_ENTRY *le;
	282	size_t off;
	283	u16 sz;
78ab59fe	284	size_t asize, new_asize, old_size;
be71b5cb KK	285	u64 new_size;
	286	typeof(ni->attr_list) *al = &ni->attr_list;
	287
	288	/*
	289	* Compute the size of the new 'le'
	290	*/
	291	sz = le_size(name_len);
78ab59fe KK	292	old_size = al->size;
	293	new_size = old_size + sz;
	294	asize = al_aligned(old_size);
be71b5cb KK	295	new_asize = al_aligned(new_size);
	296
	297	/* Scan forward to the point at which the new 'le' should be inserted. */
	298	le = al_find_le_to_insert(ni, type, name, name_len, svcn);
	299	off = PtrOffset(al->le, le);
	300
	301	if (new_size > asize) {
195c52bd	302	void *ptr = kmalloc(new_asize, GFP_NOFS);
be71b5cb KK	303
	304	if (!ptr)
	305	return -ENOMEM;
	306
	307	memcpy(ptr, al->le, off);
78ab59fe	308	memcpy(Add2Ptr(ptr, off + sz), le, old_size - off);
be71b5cb	309	le = Add2Ptr(ptr, off);
195c52bd	310	kfree(al->le);
be71b5cb KK	311	al->le = ptr;
be71b5cb KK	312	} else {
78ab59fe	313	memmove(Add2Ptr(le, sz), le, old_size - off);
be71b5cb	314	}
78ab59fe	315	*new_le = le;
be71b5cb KK	316
	317	al->size = new_size;
	318
	319	le->type = type;
	320	le->size = cpu_to_le16(sz);
	321	le->name_len = name_len;
	322	le->name_off = offsetof(struct ATTR_LIST_ENTRY, name);
	323	le->vcn = cpu_to_le64(svcn);
	324	le->ref = *ref;
	325	le->id = id;
	326	memcpy(le->name, name, sizeof(short) * name_len);
	327
be71b5cb KK	328	err = attr_set_size(ni, ATTR_LIST, NULL, 0, &al->run, new_size,
be71b5cb KK	329	&new_size, true, &attr);
78ab59fe KK	330	if (err) {
	331	/* Undo memmove above. */
	332	memmove(le, Add2Ptr(le, sz), old_size - off);
	333	al->size = old_size;
be71b5cb	334	return err;
78ab59fe KK	335	}
	336
	337	al->dirty = true;
be71b5cb KK	338
	339	if (attr && attr->non_res) {
	340	err = ntfs_sb_write_run(ni->mi.sbi, &al->run, 0, al->le,
63544672	341	al->size, 0);
be71b5cb KK	342	if (err)
be71b5cb KK	343	return err;
78ab59fe	344	al->dirty = false;
be71b5cb KK	345	}
be71b5cb KK	346
be71b5cb KK	347	return 0;
	348	}
	349
	350	/*
e8b8e97f	351	* al_remove_le - Remove @le from attribute list.
be71b5cb KK	352	*/
	353	bool al_remove_le(struct ntfs_inode ni, struct ATTR_LIST_ENTRY le)
	354	{
	355	u16 size;
	356	size_t off;
	357	typeof(ni->attr_list) *al = &ni->attr_list;
	358
	359	if (!al_is_valid_le(ni, le))
	360	return false;
	361
	362	/* Save on stack the size of 'le' */
	363	size = le16_to_cpu(le->size);
	364	off = PtrOffset(al->le, le);
	365
	366	memmove(le, Add2Ptr(le, size), al->size - (off + size));
	367
	368	al->size -= size;
	369	al->dirty = true;
	370
	371	return true;
	372	}
	373
	374	/*
e8b8e97f	375	* al_delete_le - Delete first le from the list which matches its parameters.
be71b5cb KK	376	*/
	377	bool al_delete_le(struct ntfs_inode *ni, enum ATTR_TYPE type, CLST vcn,
	378	const __le16 *name, size_t name_len,
	379	const struct MFT_REF *ref)
	380	{
	381	u16 size;
	382	struct ATTR_LIST_ENTRY *le;
	383	size_t off;
	384	typeof(ni->attr_list) *al = &ni->attr_list;
	385
e8b8e97f	386	/* Scan forward to the first le that matches the input. */
be71b5cb KK	387	le = al_find_ex(ni, NULL, type, name, name_len, &vcn);
	388	if (!le)
	389	return false;
	390
	391	off = PtrOffset(al->le, le);
	392
	393	next:
	394	if (off >= al->size)
	395	return false;
	396	if (le->type != type)
	397	return false;
	398	if (le->name_len != name_len)
	399	return false;
	400	if (name_len && ntfs_cmp_names(le_name(le), name_len, name, name_len,
	401	ni->mi.sbi->upcase, true))
	402	return false;
	403	if (le64_to_cpu(le->vcn) != vcn)
	404	return false;
	405
	406	/*
	407	* The caller specified a segment reference, so we have to
	408	* scan through the matching entries until we find that segment
	409	* reference or we run of matching entries.
	410	*/
	411	if (ref && memcmp(ref, &le->ref, sizeof(*ref))) {
	412	off += le16_to_cpu(le->size);
	413	le = Add2Ptr(al->le, off);
	414	goto next;
	415	}
	416
e8b8e97f	417	/* Save on stack the size of 'le'. */
be71b5cb	418	size = le16_to_cpu(le->size);
e8b8e97f	419	/* Delete the le. */
be71b5cb KK	420	memmove(le, Add2Ptr(le, size), al->size - (off + size));
	421
	422	al->size -= size;
	423	al->dirty = true;
	424
	425	return true;
	426	}
	427
63544672	428	int al_update(struct ntfs_inode *ni, int sync)
be71b5cb KK	429	{
	430	int err;
	431	struct ATTRIB *attr;
	432	typeof(ni->attr_list) *al = &ni->attr_list;
	433
	434	if (!al->dirty \|\| !al->size)
	435	return 0;
	436
	437	/*
e8b8e97f KA	438	* Attribute list increased on demand in al_add_le.
e8b8e97f KA	439	* Attribute list decreased here.
be71b5cb KK	440	*/
	441	err = attr_set_size(ni, ATTR_LIST, NULL, 0, &al->run, al->size, NULL,
	442	false, &attr);
	443	if (err)
	444	goto out;
	445
	446	if (!attr->non_res) {
	447	memcpy(resident_data(attr), al->le, al->size);
	448	} else {
	449	err = ntfs_sb_write_run(ni->mi.sbi, &al->run, 0, al->le,
63544672	450	al->size, sync);
be71b5cb KK	451	if (err)
	452	goto out;
	453
	454	attr->nres.valid_size = attr->nres.data_size;
	455	}
	456
	457	ni->mi.dirty = true;
	458	al->dirty = false;
	459
	460	out:
	461	return err;
	462	}