[u-boot.git] / fs / ubifs / scan.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * This file is part of UBIFS.
 *
 * Copyright (C) 2006-2008 Nokia Corporation
 *
 * Authors: Adrian Hunter
 *          Artem Bityutskiy (Битюцкий Артём)
 */

/*
 * This file implements the scan which is a general-purpose function for
 * determining what nodes are in an eraseblock. The scan is used to replay the
 * journal, to do garbage collection. for the TNC in-the-gaps method, and by
 * debugging functions.
 */

#ifdef __UBOOT__
#include <linux/err.h>
#endif
#include "ubifs.h"

/**
 * scan_padding_bytes - scan for padding bytes.
 * @buf: buffer to scan
 * @len: length of buffer
 *
 * This function returns the number of padding bytes on success and
 * %SCANNED_GARBAGE on failure.
 */
static int scan_padding_bytes(void *buf, int len)
{
	int pad_len = 0, max_pad_len = min_t(int, UBIFS_PAD_NODE_SZ, len);
	uint8_t *p = buf;

	dbg_scan("not a node");

	while (pad_len < max_pad_len && *p++ == UBIFS_PADDING_BYTE)
		pad_len += 1;

	if (!pad_len || (pad_len & 7))
		return SCANNED_GARBAGE;

	dbg_scan("%d padding bytes", pad_len);

	return pad_len;
}

/**
 * ubifs_scan_a_node - scan for a node or padding.
 * @c: UBIFS file-system description object
 * @buf: buffer to scan
 * @len: length of buffer
 * @lnum: logical eraseblock number
 * @offs: offset within the logical eraseblock
 * @quiet: print no messages
 *
 * This function returns a scanning code to indicate what was scanned.
 */
int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
		      int offs, int quiet)
{
	struct ubifs_ch *ch = buf;
	uint32_t magic;

	magic = le32_to_cpu(ch->magic);

	if (magic == 0xFFFFFFFF) {
		dbg_scan("hit empty space at LEB %d:%d", lnum, offs);
		return SCANNED_EMPTY_SPACE;
	}

	if (magic != UBIFS_NODE_MAGIC)
		return scan_padding_bytes(buf, len);

	if (len < UBIFS_CH_SZ)
		return SCANNED_GARBAGE;

	dbg_scan("scanning %s at LEB %d:%d",
		 dbg_ntype(ch->node_type), lnum, offs);

	if (ubifs_check_node(c, buf, lnum, offs, quiet, 1))
		return SCANNED_A_CORRUPT_NODE;

	if (ch->node_type == UBIFS_PAD_NODE) {
		struct ubifs_pad_node *pad = buf;
		int pad_len = le32_to_cpu(pad->pad_len);
		int node_len = le32_to_cpu(ch->len);

		/* Validate the padding node */
		if (pad_len < 0 ||
		    offs + node_len + pad_len > c->leb_size) {
			if (!quiet) {
				ubifs_err(c, "bad pad node at LEB %d:%d",
					  lnum, offs);
				ubifs_dump_node(c, pad);
			}
			return SCANNED_A_BAD_PAD_NODE;
		}

		/* Make the node pads to 8-byte boundary */
		if ((node_len + pad_len) & 7) {
			if (!quiet)
				ubifs_err(c, "bad padding length %d - %d",
					  offs, offs + node_len + pad_len);
			return SCANNED_A_BAD_PAD_NODE;
		}

		dbg_scan("%d bytes padded at LEB %d:%d, offset now %d", pad_len,
			 lnum, offs, ALIGN(offs + node_len + pad_len, 8));

		return node_len + pad_len;
	}

	return SCANNED_A_NODE;
}

/**
 * ubifs_start_scan - create LEB scanning information at start of scan.
 * @c: UBIFS file-system description object
 * @lnum: logical eraseblock number
 * @offs: offset to start at (usually zero)
 * @sbuf: scan buffer (must be c->leb_size)
 *
 * This function returns the scanned information on success and a negative error
 * code on failure.
 */
struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum,
					int offs, void *sbuf)
{
	struct ubifs_scan_leb *sleb;
	int err;

	dbg_scan("scan LEB %d:%d", lnum, offs);

	sleb = kzalloc(sizeof(struct ubifs_scan_leb), GFP_NOFS);
	if (!sleb)
		return ERR_PTR(-ENOMEM);

	sleb->lnum = lnum;
	INIT_LIST_HEAD(&sleb->nodes);
	sleb->buf = sbuf;

	err = ubifs_leb_read(c, lnum, sbuf + offs, offs, c->leb_size - offs, 0);
	if (err && err != -EBADMSG) {
		ubifs_err(c, "cannot read %d bytes from LEB %d:%d, error %d",
			  c->leb_size - offs, lnum, offs, err);
		kfree(sleb);
		return ERR_PTR(err);
	}

	/*
	 * Note, we ignore integrity errors (EBASMSG) because all the nodes are
	 * protected by CRC checksums.
	 */
	return sleb;
}

/**
 * ubifs_end_scan - update LEB scanning information at end of scan.
 * @c: UBIFS file-system description object
 * @sleb: scanning information
 * @lnum: logical eraseblock number
 * @offs: offset to start at (usually zero)
 */
void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
		    int lnum, int offs)
{
	lnum = lnum;
	dbg_scan("stop scanning LEB %d at offset %d", lnum, offs);
	ubifs_assert(offs % c->min_io_size == 0);

	sleb->endpt = ALIGN(offs, c->min_io_size);
}

/**
 * ubifs_add_snod - add a scanned node to LEB scanning information.
 * @c: UBIFS file-system description object
 * @sleb: scanning information
 * @buf: buffer containing node
 * @offs: offset of node on flash
 *
 * This function returns %0 on success and a negative error code on failure.
 */
int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
		   void *buf, int offs)
{
	struct ubifs_ch *ch = buf;
	struct ubifs_ino_node *ino = buf;
	struct ubifs_scan_node *snod;

	snod = kmalloc(sizeof(struct ubifs_scan_node), GFP_NOFS);
	if (!snod)
		return -ENOMEM;

	snod->sqnum = le64_to_cpu(ch->sqnum);
	snod->type = ch->node_type;
	snod->offs = offs;
	snod->len = le32_to_cpu(ch->len);
	snod->node = buf;

	switch (ch->node_type) {
	case UBIFS_INO_NODE:
	case UBIFS_DENT_NODE:
	case UBIFS_XENT_NODE:
	case UBIFS_DATA_NODE:
		/*
		 * The key is in the same place in all keyed
		 * nodes.
		 */
		key_read(c, &ino->key, &snod->key);
		break;
	default:
		invalid_key_init(c, &snod->key);
		break;
	}
	list_add_tail(&snod->list, &sleb->nodes);
	sleb->nodes_cnt += 1;
	return 0;
}

/**
 * ubifs_scanned_corruption - print information after UBIFS scanned corruption.
 * @c: UBIFS file-system description object
 * @lnum: LEB number of corruption
 * @offs: offset of corruption
 * @buf: buffer containing corruption
 */
void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs,
			      void *buf)
{
	int len;

	ubifs_err(c, "corruption at LEB %d:%d", lnum, offs);
	len = c->leb_size - offs;
	if (len > 8192)
		len = 8192;
	ubifs_err(c, "first %d bytes from LEB %d:%d", len, lnum, offs);
	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 4, buf, len, 1);
}

/**
 * ubifs_scan - scan a logical eraseblock.
 * @c: UBIFS file-system description object
 * @lnum: logical eraseblock number
 * @offs: offset to start at (usually zero)
 * @sbuf: scan buffer (must be of @c->leb_size bytes in size)
 * @quiet: print no messages
 *
 * This function scans LEB number @lnum and returns complete information about
 * its contents. Returns the scanned information in case of success and,
 * %-EUCLEAN if the LEB neads recovery, and other negative error codes in case
 * of failure.
 *
 * If @quiet is non-zero, this function does not print large and scary
 * error messages and flash dumps in case of errors.
 */
struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum,
				  int offs, void *sbuf, int quiet)
{
	void *buf = sbuf + offs;
	int err, len = c->leb_size - offs;
	struct ubifs_scan_leb *sleb;

	sleb = ubifs_start_scan(c, lnum, offs, sbuf);
	if (IS_ERR(sleb))
		return sleb;

	while (len >= 8) {
		struct ubifs_ch *ch = buf;
		int node_len, ret;

		dbg_scan("look at LEB %d:%d (%d bytes left)",
			 lnum, offs, len);

		cond_resched();

		ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
		if (ret > 0) {
			/* Padding bytes or a valid padding node */
			offs += ret;
			buf += ret;
			len -= ret;
			continue;
		}

		if (ret == SCANNED_EMPTY_SPACE)
			/* Empty space is checked later */
			break;

		switch (ret) {
		case SCANNED_GARBAGE:
			ubifs_err(c, "garbage");
			goto corrupted;
		case SCANNED_A_NODE:
			break;
		case SCANNED_A_CORRUPT_NODE:
		case SCANNED_A_BAD_PAD_NODE:
			ubifs_err(c, "bad node");
			goto corrupted;
		default:
			ubifs_err(c, "unknown");
			err = -EINVAL;
			goto error;
		}

		err = ubifs_add_snod(c, sleb, buf, offs);
		if (err)
			goto error;

		node_len = ALIGN(le32_to_cpu(ch->len), 8);
		offs += node_len;
		buf += node_len;
		len -= node_len;
	}

	if (offs % c->min_io_size) {
		if (!quiet)
			ubifs_err(c, "empty space starts at non-aligned offset %d",
				  offs);
		goto corrupted;
	}

	ubifs_end_scan(c, sleb, lnum, offs);

	for (; len > 4; offs += 4, buf = buf + 4, len -= 4)
		if (*(uint32_t *)buf != 0xffffffff)
			break;
	for (; len; offs++, buf++, len--)
		if (*(uint8_t *)buf != 0xff) {
			if (!quiet)
				ubifs_err(c, "corrupt empty space at LEB %d:%d",
					  lnum, offs);
			goto corrupted;
		}

	return sleb;

corrupted:
	if (!quiet) {
		ubifs_scanned_corruption(c, lnum, offs, buf);
		ubifs_err(c, "LEB %d scanning failed", lnum);
	}
	err = -EUCLEAN;
	ubifs_scan_destroy(sleb);
	return ERR_PTR(err);

error:
	ubifs_err(c, "LEB %d scanning failed, error %d", lnum, err);
	ubifs_scan_destroy(sleb);
	return ERR_PTR(err);
}

/**
 * ubifs_scan_destroy - destroy LEB scanning information.
 * @sleb: scanning information to free
 */
void ubifs_scan_destroy(struct ubifs_scan_leb *sleb)
{
	struct ubifs_scan_node *node;
	struct list_head *head;

	head = &sleb->nodes;
	while (!list_empty(head)) {
		node = list_entry(head->next, struct ubifs_scan_node, list);
		list_del(&node->list);
		kfree(node);
	}
	kfree(sleb);
}
Commit	Line	Data
83d290c5	1	// SPDX-License-Identifier: GPL-2.0+
9eefe2a2 SR	2	/*
	3	* This file is part of UBIFS.
	4	*
	5	* Copyright (C) 2006-2008 Nokia Corporation
	6	*
9eefe2a2 SR	7	* Authors: Adrian Hunter
	8	* Artem Bityutskiy (Битюцкий Артём)
	9	*/
	10
	11	/*
	12	* This file implements the scan which is a general-purpose function for
	13	* determining what nodes are in an eraseblock. The scan is used to replay the
	14	* journal, to do garbage collection. for the TNC in-the-gaps method, and by
	15	* debugging functions.
	16	*/
	17
ff94bc40 HS	18	#ifdef __UBOOT__
	19	#include <linux/err.h>
	20	#endif
9eefe2a2 SR	21	#include "ubifs.h"
	22
	23	/**
	24	* scan_padding_bytes - scan for padding bytes.
	25	* @buf: buffer to scan
	26	* @len: length of buffer
	27	*
	28	* This function returns the number of padding bytes on success and
	29	* %SCANNED_GARBAGE on failure.
	30	*/
	31	static int scan_padding_bytes(void *buf, int len)
	32	{
	33	int pad_len = 0, max_pad_len = min_t(int, UBIFS_PAD_NODE_SZ, len);
	34	uint8_t *p = buf;
	35
	36	dbg_scan("not a node");
	37
	38	while (pad_len < max_pad_len && *p++ == UBIFS_PADDING_BYTE)
	39	pad_len += 1;
	40
	41	if (!pad_len \|\| (pad_len & 7))
	42	return SCANNED_GARBAGE;
	43
	44	dbg_scan("%d padding bytes", pad_len);
	45
	46	return pad_len;
	47	}
	48
	49	/**
	50	* ubifs_scan_a_node - scan for a node or padding.
	51	* @c: UBIFS file-system description object
	52	* @buf: buffer to scan
	53	* @len: length of buffer
	54	* @lnum: logical eraseblock number
	55	* @offs: offset within the logical eraseblock
	56	* @quiet: print no messages
	57	*
	58	* This function returns a scanning code to indicate what was scanned.
	59	*/
	60	int ubifs_scan_a_node(const struct ubifs_info c, void buf, int len, int lnum,
	61	int offs, int quiet)
	62	{
	63	struct ubifs_ch *ch = buf;
	64	uint32_t magic;
	65
	66	magic = le32_to_cpu(ch->magic);
	67
	68	if (magic == 0xFFFFFFFF) {
ff94bc40	69	dbg_scan("hit empty space at LEB %d:%d", lnum, offs);
9eefe2a2 SR	70	return SCANNED_EMPTY_SPACE;
	71	}
	72
	73	if (magic != UBIFS_NODE_MAGIC)
	74	return scan_padding_bytes(buf, len);
	75
	76	if (len < UBIFS_CH_SZ)
	77	return SCANNED_GARBAGE;
	78
ff94bc40 HS	79	dbg_scan("scanning %s at LEB %d:%d",
ff94bc40 HS	80	dbg_ntype(ch->node_type), lnum, offs);
9eefe2a2 SR	81
	82	if (ubifs_check_node(c, buf, lnum, offs, quiet, 1))
	83	return SCANNED_A_CORRUPT_NODE;
	84
	85	if (ch->node_type == UBIFS_PAD_NODE) {
	86	struct ubifs_pad_node *pad = buf;
	87	int pad_len = le32_to_cpu(pad->pad_len);
	88	int node_len = le32_to_cpu(ch->len);
	89
	90	/* Validate the padding node */
	91	if (pad_len < 0 \|\|
	92	offs + node_len + pad_len > c->leb_size) {
	93	if (!quiet) {
0195a7bb	94	ubifs_err(c, "bad pad node at LEB %d:%d",
9eefe2a2	95	lnum, offs);
ff94bc40	96	ubifs_dump_node(c, pad);
9eefe2a2 SR	97	}
	98	return SCANNED_A_BAD_PAD_NODE;
	99	}
	100
	101	/* Make the node pads to 8-byte boundary */
	102	if ((node_len + pad_len) & 7) {
ff94bc40	103	if (!quiet)
0195a7bb	104	ubifs_err(c, "bad padding length %d - %d",
ff94bc40	105	offs, offs + node_len + pad_len);
9eefe2a2 SR	106	return SCANNED_A_BAD_PAD_NODE;
	107	}
	108
ff94bc40 HS	109	dbg_scan("%d bytes padded at LEB %d:%d, offset now %d", pad_len,
ff94bc40 HS	110	lnum, offs, ALIGN(offs + node_len + pad_len, 8));
9eefe2a2 SR	111
	112	return node_len + pad_len;
	113	}
	114
	115	return SCANNED_A_NODE;
	116	}
	117
	118	/**
	119	* ubifs_start_scan - create LEB scanning information at start of scan.
	120	* @c: UBIFS file-system description object
	121	* @lnum: logical eraseblock number
	122	* @offs: offset to start at (usually zero)
	123	* @sbuf: scan buffer (must be c->leb_size)
	124	*
0195a7bb HS	125	* This function returns the scanned information on success and a negative error
0195a7bb HS	126	* code on failure.
9eefe2a2 SR	127	*/
	128	struct ubifs_scan_leb ubifs_start_scan(const struct ubifs_info c, int lnum,
	129	int offs, void *sbuf)
	130	{
	131	struct ubifs_scan_leb *sleb;
	132	int err;
	133
	134	dbg_scan("scan LEB %d:%d", lnum, offs);
	135
	136	sleb = kzalloc(sizeof(struct ubifs_scan_leb), GFP_NOFS);
	137	if (!sleb)
	138	return ERR_PTR(-ENOMEM);
	139
	140	sleb->lnum = lnum;
	141	INIT_LIST_HEAD(&sleb->nodes);
	142	sleb->buf = sbuf;
	143
ff94bc40	144	err = ubifs_leb_read(c, lnum, sbuf + offs, offs, c->leb_size - offs, 0);
9eefe2a2	145	if (err && err != -EBADMSG) {
0195a7bb	146	ubifs_err(c, "cannot read %d bytes from LEB %d:%d, error %d",
ff94bc40	147	c->leb_size - offs, lnum, offs, err);
9eefe2a2 SR	148	kfree(sleb);
	149	return ERR_PTR(err);
	150	}
	151
0195a7bb HS	152	/*
	153	* Note, we ignore integrity errors (EBASMSG) because all the nodes are
	154	* protected by CRC checksums.
	155	*/
9eefe2a2 SR	156	return sleb;
	157	}
	158
	159	/**
	160	* ubifs_end_scan - update LEB scanning information at end of scan.
	161	* @c: UBIFS file-system description object
	162	* @sleb: scanning information
	163	* @lnum: logical eraseblock number
	164	* @offs: offset to start at (usually zero)
9eefe2a2 SR	165	*/
	166	void ubifs_end_scan(const struct ubifs_info c, struct ubifs_scan_leb sleb,
	167	int lnum, int offs)
	168	{
	169	lnum = lnum;
	170	dbg_scan("stop scanning LEB %d at offset %d", lnum, offs);
	171	ubifs_assert(offs % c->min_io_size == 0);
	172
	173	sleb->endpt = ALIGN(offs, c->min_io_size);
	174	}
	175
	176	/**
	177	* ubifs_add_snod - add a scanned node to LEB scanning information.
	178	* @c: UBIFS file-system description object
	179	* @sleb: scanning information
	180	* @buf: buffer containing node
	181	* @offs: offset of node on flash
	182	*
	183	* This function returns %0 on success and a negative error code on failure.
	184	*/
	185	int ubifs_add_snod(const struct ubifs_info c, struct ubifs_scan_leb sleb,
	186	void *buf, int offs)
	187	{
	188	struct ubifs_ch *ch = buf;
	189	struct ubifs_ino_node *ino = buf;
	190	struct ubifs_scan_node *snod;
	191
ff94bc40	192	snod = kmalloc(sizeof(struct ubifs_scan_node), GFP_NOFS);
9eefe2a2 SR	193	if (!snod)
	194	return -ENOMEM;
	195
	196	snod->sqnum = le64_to_cpu(ch->sqnum);
	197	snod->type = ch->node_type;
	198	snod->offs = offs;
	199	snod->len = le32_to_cpu(ch->len);
	200	snod->node = buf;
	201
	202	switch (ch->node_type) {
	203	case UBIFS_INO_NODE:
	204	case UBIFS_DENT_NODE:
	205	case UBIFS_XENT_NODE:
	206	case UBIFS_DATA_NODE:
9eefe2a2 SR	207	/*
	208	* The key is in the same place in all keyed
	209	* nodes.
	210	*/
	211	key_read(c, &ino->key, &snod->key);
	212	break;
ff94bc40 HS	213	default:
	214	invalid_key_init(c, &snod->key);
	215	break;
9eefe2a2 SR	216	}
	217	list_add_tail(&snod->list, &sleb->nodes);
	218	sleb->nodes_cnt += 1;
	219	return 0;
	220	}
	221
	222	/**
	223	* ubifs_scanned_corruption - print information after UBIFS scanned corruption.
	224	* @c: UBIFS file-system description object
	225	* @lnum: LEB number of corruption
	226	* @offs: offset of corruption
	227	* @buf: buffer containing corruption
	228	*/
	229	void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs,
	230	void *buf)
	231	{
	232	int len;
	233
0195a7bb	234	ubifs_err(c, "corruption at LEB %d:%d", lnum, offs);
9eefe2a2	235	len = c->leb_size - offs;
ff94bc40 HS	236	if (len > 8192)
ff94bc40 HS	237	len = 8192;
0195a7bb	238	ubifs_err(c, "first %d bytes from LEB %d:%d", len, lnum, offs);
9eefe2a2 SR	239	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 4, buf, len, 1);
	240	}
	241
	242	/**
	243	* ubifs_scan - scan a logical eraseblock.
	244	* @c: UBIFS file-system description object
	245	* @lnum: logical eraseblock number
	246	* @offs: offset to start at (usually zero)
ff94bc40 HS	247	* @sbuf: scan buffer (must be of @c->leb_size bytes in size)
ff94bc40 HS	248	* @quiet: print no messages
9eefe2a2 SR	249	*
9eefe2a2 SR	250	* This function scans LEB number @lnum and returns complete information about
0195a7bb	251	* its contents. Returns the scanned information in case of success and,
ff94bc40 HS	252	* %-EUCLEAN if the LEB neads recovery, and other negative error codes in case
	253	* of failure.
	254	*
	255	* If @quiet is non-zero, this function does not print large and scary
	256	* error messages and flash dumps in case of errors.
9eefe2a2 SR	257	*/
9eefe2a2 SR	258	struct ubifs_scan_leb ubifs_scan(const struct ubifs_info c, int lnum,
ff94bc40	259	int offs, void *sbuf, int quiet)
9eefe2a2 SR	260	{
	261	void *buf = sbuf + offs;
	262	int err, len = c->leb_size - offs;
	263	struct ubifs_scan_leb *sleb;
	264
	265	sleb = ubifs_start_scan(c, lnum, offs, sbuf);
	266	if (IS_ERR(sleb))
	267	return sleb;
	268
	269	while (len >= 8) {
	270	struct ubifs_ch *ch = buf;
	271	int node_len, ret;
	272
	273	dbg_scan("look at LEB %d:%d (%d bytes left)",
	274	lnum, offs, len);
	275
	276	cond_resched();
	277
ff94bc40	278	ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
9eefe2a2 SR	279	if (ret > 0) {
	280	/* Padding bytes or a valid padding node */
	281	offs += ret;
	282	buf += ret;
	283	len -= ret;
	284	continue;
	285	}
	286
	287	if (ret == SCANNED_EMPTY_SPACE)
	288	/* Empty space is checked later */
	289	break;
	290
	291	switch (ret) {
	292	case SCANNED_GARBAGE:
0195a7bb	293	ubifs_err(c, "garbage");
9eefe2a2 SR	294	goto corrupted;
	295	case SCANNED_A_NODE:
	296	break;
	297	case SCANNED_A_CORRUPT_NODE:
	298	case SCANNED_A_BAD_PAD_NODE:
0195a7bb	299	ubifs_err(c, "bad node");
9eefe2a2 SR	300	goto corrupted;
9eefe2a2 SR	301	default:
0195a7bb	302	ubifs_err(c, "unknown");
ff94bc40 HS	303	err = -EINVAL;
ff94bc40 HS	304	goto error;
9eefe2a2 SR	305	}
	306
	307	err = ubifs_add_snod(c, sleb, buf, offs);
	308	if (err)
	309	goto error;
	310
	311	node_len = ALIGN(le32_to_cpu(ch->len), 8);
	312	offs += node_len;
	313	buf += node_len;
	314	len -= node_len;
	315	}
	316
ff94bc40 HS	317	if (offs % c->min_io_size) {
ff94bc40 HS	318	if (!quiet)
0195a7bb	319	ubifs_err(c, "empty space starts at non-aligned offset %d",
ff94bc40	320	offs);
9eefe2a2	321	goto corrupted;
ff94bc40	322	}
9eefe2a2 SR	323
	324	ubifs_end_scan(c, sleb, lnum, offs);
	325
	326	for (; len > 4; offs += 4, buf = buf + 4, len -= 4)
	327	if ((uint32_t )buf != 0xffffffff)
	328	break;
	329	for (; len; offs++, buf++, len--)
	330	if ((uint8_t )buf != 0xff) {
ff94bc40	331	if (!quiet)
0195a7bb	332	ubifs_err(c, "corrupt empty space at LEB %d:%d",
ff94bc40	333	lnum, offs);
9eefe2a2 SR	334	goto corrupted;
	335	}
	336
	337	return sleb;
	338
	339	corrupted:
ff94bc40 HS	340	if (!quiet) {
ff94bc40 HS	341	ubifs_scanned_corruption(c, lnum, offs, buf);
0195a7bb	342	ubifs_err(c, "LEB %d scanning failed", lnum);
ff94bc40	343	}
9eefe2a2	344	err = -EUCLEAN;
ff94bc40 HS	345	ubifs_scan_destroy(sleb);
	346	return ERR_PTR(err);
	347
9eefe2a2	348	error:
0195a7bb	349	ubifs_err(c, "LEB %d scanning failed, error %d", lnum, err);
9eefe2a2 SR	350	ubifs_scan_destroy(sleb);
	351	return ERR_PTR(err);
	352	}
	353
	354	/**
	355	* ubifs_scan_destroy - destroy LEB scanning information.
	356	* @sleb: scanning information to free
	357	*/
	358	void ubifs_scan_destroy(struct ubifs_scan_leb *sleb)
	359	{
	360	struct ubifs_scan_node *node;
	361	struct list_head *head;
	362
	363	head = &sleb->nodes;
	364	while (!list_empty(head)) {
	365	node = list_entry(head->next, struct ubifs_scan_node, list);
	366	list_del(&node->list);
	367	kfree(node);
	368	}
	369	kfree(sleb);
	370	}