Re: [syzbot] [udf?] KASAN: slab-out-of-bounds Read in udf_get_filelongad (2)

[Zhao Mengmeng <zhaomzhao@126.com>]

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#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 67784a74e258

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diff --git a/fs/udf/balloc.c b/fs/udf/balloc.c
index d8fc11765d61..b216c43cf433 100644
--- a/fs/udf/balloc.c
+++ b/fs/udf/balloc.c
@@ -384,7 +384,7 @@ static void udf_table_free_blocks(struct super_block *sb,
 	epos.bh = oepos.bh = NULL;
 
 	while (count &&
-	       (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
+	       !udf_next_aext(table, &epos, &eloc, &elen, &etype, 1)) {
 		if (((eloc.logicalBlockNum +
 			(elen >> sb->s_blocksize_bits)) == start)) {
 			if ((0x3FFFFFFF - elen) <
@@ -517,7 +517,7 @@ static int udf_table_prealloc_blocks(struct super_block *sb,
 	eloc.logicalBlockNum = 0xFFFFFFFF;
 
 	while (first_block != eloc.logicalBlockNum &&
-	       (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
+	       !udf_next_aext(table, &epos, &eloc, &elen, &etype, 1)) {
 		udf_debug("eloc=%u, elen=%u, first_block=%u\n",
 			  eloc.logicalBlockNum, elen, first_block);
 		; /* empty loop body */
@@ -584,7 +584,7 @@ static udf_pblk_t udf_table_new_block(struct super_block *sb,
 	epos.bh = goal_epos.bh = NULL;
 
 	while (spread &&
-	       (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
+	       !udf_next_aext(table, &epos, &eloc, &elen, &etype, 1)) {
 		if (goal >= eloc.logicalBlockNum) {
 			if (goal < eloc.logicalBlockNum +
 					(elen >> sb->s_blocksize_bits))
diff --git a/fs/udf/directory.c b/fs/udf/directory.c
index 93153665eb37..cb40e1ade9f6 100644
--- a/fs/udf/directory.c
+++ b/fs/udf/directory.c
@@ -166,13 +166,16 @@ static struct buffer_head *udf_fiiter_bread_blk(struct udf_fileident_iter *iter)
  */
 static int udf_fiiter_advance_blk(struct udf_fileident_iter *iter)
 {
+	int8_t etype;
+	int err = 0;
 	iter->loffset++;
 	if (iter->loffset < DIV_ROUND_UP(iter->elen, 1<<iter->dir->i_blkbits))
 		return 0;
 
 	iter->loffset = 0;
-	if (udf_next_aext(iter->dir, &iter->epos, &iter->eloc, &iter->elen, 1)
-			!= (EXT_RECORDED_ALLOCATED >> 30)) {
+	err = udf_next_aext(iter->dir, &iter->epos, &iter->eloc, &iter->elen,
+			    &etype, 1);
+	if (err || etype != (EXT_RECORDED_ALLOCATED >> 30)) {
 		if (iter->pos == iter->dir->i_size) {
 			iter->elen = 0;
 			return 0;
@@ -240,6 +243,7 @@ int udf_fiiter_init(struct udf_fileident_iter *iter, struct inode *dir,
 {
 	struct udf_inode_info *iinfo = UDF_I(dir);
 	int err = 0;
+	int8_t etype;
 
 	iter->dir = dir;
 	iter->bh[0] = iter->bh[1] = NULL;
@@ -259,9 +263,9 @@ int udf_fiiter_init(struct udf_fileident_iter *iter, struct inode *dir,
 		goto out;
 	}
 
-	if (inode_bmap(dir, iter->pos >> dir->i_blkbits, &iter->epos,
-		       &iter->eloc, &iter->elen, &iter->loffset) !=
-	    (EXT_RECORDED_ALLOCATED >> 30)) {
+	err = inode_bmap(dir, iter->pos >> dir->i_blkbits, &iter->epos, &iter->eloc,
+		   &iter->elen, &iter->loffset, &etype);
+	if (err || etype != (EXT_RECORDED_ALLOCATED >> 30)) {
 		if (pos == dir->i_size)
 			return 0;
 		udf_err(dir->i_sb,
@@ -457,6 +461,7 @@ int udf_fiiter_append_blk(struct udf_fileident_iter *iter)
 	sector_t block;
 	uint32_t old_elen = iter->elen;
 	int err;
+	int8_t etype;
 
 	if (WARN_ON_ONCE(iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB))
 		return -EINVAL;
@@ -471,8 +476,9 @@ int udf_fiiter_append_blk(struct udf_fileident_iter *iter)
 		udf_fiiter_update_elen(iter, old_elen);
 		return err;
 	}
-	if (inode_bmap(iter->dir, block, &iter->epos, &iter->eloc, &iter->elen,
-		       &iter->loffset) != (EXT_RECORDED_ALLOCATED >> 30)) {
+	err = inode_bmap(iter->dir, block, &iter->epos, &iter->eloc, &iter->elen,
+		   &iter->loffset, &etype);
+	if (err || etype != (EXT_RECORDED_ALLOCATED >> 30)) {
 		udf_err(iter->dir->i_sb,
 			"block %llu not allocated in directory (ino %lu)\n",
 			(unsigned long long)block, iter->dir->i_ino);
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 4726a4d014b6..f1b8f0a0d202 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -418,10 +418,11 @@ static int udf_map_block(struct inode *inode, struct udf_map_rq *map)
 		uint32_t elen;
 		sector_t offset;
 		struct extent_position epos = {};
+		int8_t etype;
 
 		down_read(&iinfo->i_data_sem);
-		if (inode_bmap(inode, map->lblk, &epos, &eloc, &elen, &offset)
-				== (EXT_RECORDED_ALLOCATED >> 30)) {
+		inode_bmap(inode, map->lblk, &epos, &eloc, &elen, &offset, &etype);
+		if (etype == (EXT_RECORDED_ALLOCATED >> 30)) {
 			map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc,
 							offset);
 			map->oflags |= UDF_BLK_MAPPED;
@@ -545,6 +546,7 @@ static int udf_do_extend_file(struct inode *inode,
 	} else {
 		struct kernel_lb_addr tmploc;
 		uint32_t tmplen;
+		int8_t tmptype;
 
 		udf_write_aext(inode, last_pos, &last_ext->extLocation,
 				last_ext->extLength, 1);
@@ -555,7 +557,7 @@ static int udf_do_extend_file(struct inode *inode,
 		 * empty indirect extent.
 		 */
 		if (new_block_bytes)
-			udf_next_aext(inode, last_pos, &tmploc, &tmplen, 0);
+			udf_next_aext(inode, last_pos, &tmploc, &tmplen, &tmptype, 0);
 	}
 	iinfo->i_lenExtents += add;
 
@@ -659,8 +661,10 @@ static int udf_extend_file(struct inode *inode, loff_t newsize)
 	 */
 	udf_discard_prealloc(inode);
 
-	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
-	within_last_ext = (etype != -1);
+	err = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset, &etype);
+	if (err < 0 && err != -ENODATA)
+		goto out;
+	within_last_ext = (!err);
 	/* We don't expect extents past EOF... */
 	WARN_ON_ONCE(within_last_ext &&
 		     elen > ((loff_t)offset + 1) << inode->i_blkbits);
@@ -674,8 +678,8 @@ static int udf_extend_file(struct inode *inode, loff_t newsize)
 		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
 	} else {
 		epos.offset -= adsize;
-		etype = udf_next_aext(inode, &epos, &extent.extLocation,
-				      &extent.extLength, 0);
+		udf_next_aext(inode, &epos, &extent.extLocation,
+				&extent.extLength, &etype, 0);
 		extent.extLength |= etype << 30;
 	}
 
@@ -712,7 +716,7 @@ static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
 	loff_t lbcount = 0, b_off = 0;
 	udf_pblk_t newblocknum;
 	sector_t offset = 0;
-	int8_t etype;
+	int8_t etype, tmpetype;
 	struct udf_inode_info *iinfo = UDF_I(inode);
 	udf_pblk_t goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
 	int lastblock = 0;
@@ -748,8 +752,8 @@ static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
 		prev_epos.offset = cur_epos.offset;
 		cur_epos.offset = next_epos.offset;
 
-		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 1);
-		if (etype == -1)
+		ret = udf_next_aext(inode, &next_epos, &eloc, &elen, &etype, 1);
+		if (ret)
 			break;
 
 		c = !c;
@@ -771,8 +775,8 @@ static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
 	 * Move prev_epos and cur_epos into indirect extent if we are at
 	 * the pointer to it
 	 */
-	udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, 0);
-	udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, 0);
+	udf_next_aext(inode, &prev_epos, &tmpeloc, &tmpelen, &tmpetype, 0);
+	udf_next_aext(inode, &cur_epos, &tmpeloc, &tmpelen, &tmpetype, 0);
 
 	/* if the extent is allocated and recorded, return the block
 	   if the extent is not a multiple of the blocksize, round up */
@@ -793,7 +797,7 @@ static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
 	}
 
 	/* Are we beyond EOF and preallocated extent? */
-	if (etype == -1) {
+	if (ret < 0) {
 		loff_t hole_len;
 
 		isBeyondEOF = true;
@@ -846,8 +850,7 @@ static int inode_getblk(struct inode *inode, struct udf_map_rq *map)
 
 		/* if the current block is located in an extent,
 		   read the next extent */
-		etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0);
-		if (etype != -1) {
+		if (!udf_next_aext(inode, &next_epos, &eloc, &elen, &etype, 0)) {
 			laarr[c + 1].extLength = (etype << 30) | elen;
 			laarr[c + 1].extLocation = eloc;
 			count++;
@@ -1172,6 +1175,7 @@ static int udf_update_extents(struct inode *inode, struct kernel_long_ad *laarr,
 	int start = 0, i;
 	struct kernel_lb_addr tmploc;
 	uint32_t tmplen;
+	int8_t tmptype;
 	int err;
 
 	if (startnum > endnum) {
@@ -1190,13 +1194,13 @@ static int udf_update_extents(struct inode *inode, struct kernel_long_ad *laarr,
 			if (err < 0)
 				return err;
 			udf_next_aext(inode, epos, &laarr[i].extLocation,
-				      &laarr[i].extLength, 1);
+				      &laarr[i].extLength, &tmptype, 1);
 			start++;
 		}
 	}
 
 	for (i = start; i < endnum; i++) {
-		udf_next_aext(inode, epos, &tmploc, &tmplen, 0);
+		udf_next_aext(inode, epos, &tmploc, &tmplen, &tmptype, 0);
 		udf_write_aext(inode, epos, &laarr[i].extLocation,
 			       laarr[i].extLength, 1);
 	}
@@ -1955,6 +1959,7 @@ int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
 	struct extent_position nepos;
 	struct kernel_lb_addr neloc;
 	int ver, adsize;
+	int err = 0;
 
 	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
 		adsize = sizeof(struct short_ad);
@@ -1999,10 +2004,12 @@ int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
 	if (epos->offset + adsize > sb->s_blocksize) {
 		struct kernel_lb_addr cp_loc;
 		uint32_t cp_len;
-		int cp_type;
+		int8_t cp_type;
 
 		epos->offset -= adsize;
-		cp_type = udf_current_aext(inode, epos, &cp_loc, &cp_len, 0);
+		err = udf_current_aext(inode, epos, &cp_loc, &cp_len, &cp_type, 0);
+		if (err < 0)
+			goto err_out;
 		cp_len |= ((uint32_t)cp_type) << 30;
 
 		__udf_add_aext(inode, &nepos, &cp_loc, cp_len, 1);
@@ -2017,6 +2024,9 @@ int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
 	*epos = nepos;
 
 	return 0;
+err_out:
+	brelse(epos->bh);
+	return err;
 }
 
 /*
@@ -2162,21 +2172,24 @@ void udf_write_aext(struct inode *inode, struct extent_position *epos,
  */
 #define UDF_MAX_INDIR_EXTS 16
 
-int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
-		     struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
+int udf_next_aext(struct inode *inode, struct extent_position *epos,
+		  struct kernel_lb_addr *eloc, uint32_t *elen, int8_t *etype,
+		  int inc)
 {
-	int8_t etype;
 	unsigned int indirections = 0;
+	int err = 0;
+
+	while ((err = udf_current_aext(inode, epos, eloc, elen, etype, inc))) {
+		if (err || *etype != (EXT_NEXT_EXTENT_ALLOCDESCS >> 30))
+			break;
 
-	while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) ==
-	       (EXT_NEXT_EXTENT_ALLOCDESCS >> 30)) {
 		udf_pblk_t block;
 
 		if (++indirections > UDF_MAX_INDIR_EXTS) {
 			udf_err(inode->i_sb,
 				"too many indirect extents in inode %lu\n",
 				inode->i_ino);
-			return -1;
+			return -EFSCORRUPTED;
 		}
 
 		epos->block = *eloc;
@@ -2186,18 +2199,18 @@ int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
 		epos->bh = sb_bread(inode->i_sb, block);
 		if (!epos->bh) {
 			udf_debug("reading block %u failed!\n", block);
-			return -1;
+			return -EIO;
 		}
 	}
 
-	return etype;
+	return err;
 }
 
-int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
-			struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
+int udf_current_aext(struct inode *inode, struct extent_position *epos,
+		     struct kernel_lb_addr *eloc, uint32_t *elen, int8_t *etype,
+		     int inc)
 {
 	int alen;
-	int8_t etype;
 	uint8_t *ptr;
 	struct short_ad *sad;
 	struct long_ad *lad;
@@ -2224,8 +2237,8 @@ int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
 	case ICBTAG_FLAG_AD_SHORT:
 		sad = udf_get_fileshortad(ptr, alen, &epos->offset, inc);
 		if (!sad)
-			return -1;
-		etype = le32_to_cpu(sad->extLength) >> 30;
+			return -ENODATA;
+		*etype = le32_to_cpu(sad->extLength) >> 30;
 		eloc->logicalBlockNum = le32_to_cpu(sad->extPosition);
 		eloc->partitionReferenceNum =
 				iinfo->i_location.partitionReferenceNum;
@@ -2234,17 +2247,17 @@ int8_t udf_current_aext(struct inode *inode, struct extent_position *epos,
 	case ICBTAG_FLAG_AD_LONG:
 		lad = udf_get_filelongad(ptr, alen, &epos->offset, inc);
 		if (!lad)
-			return -1;
-		etype = le32_to_cpu(lad->extLength) >> 30;
+			return -ENODATA;
+		*etype = le32_to_cpu(lad->extLength) >> 30;
 		*eloc = lelb_to_cpu(lad->extLocation);
 		*elen = le32_to_cpu(lad->extLength) & UDF_EXTENT_LENGTH_MASK;
 		break;
 	default:
 		udf_debug("alloc_type = %u unsupported\n", iinfo->i_alloc_type);
-		return -1;
+		return -EINVAL;
 	}
 
-	return etype;
+	return 0;
 }
 
 static int udf_insert_aext(struct inode *inode, struct extent_position epos,
@@ -2258,7 +2271,7 @@ static int udf_insert_aext(struct inode *inode, struct extent_position epos,
 	if (epos.bh)
 		get_bh(epos.bh);
 
-	while ((etype = udf_next_aext(inode, &epos, &oeloc, &oelen, 0)) != -1) {
+	while (!udf_next_aext(inode, &epos, &oeloc, &oelen, &etype, 0)) {
 		udf_write_aext(inode, &epos, &neloc, nelen, 1);
 		neloc = oeloc;
 		nelen = (etype << 30) | oelen;
@@ -2293,10 +2306,10 @@ int8_t udf_delete_aext(struct inode *inode, struct extent_position epos)
 		adsize = 0;
 
 	oepos = epos;
-	if (udf_next_aext(inode, &epos, &eloc, &elen, 1) == -1)
+	if (udf_next_aext(inode, &epos, &eloc, &elen, &etype, 1))
 		return -1;
 
-	while ((etype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
+	while (!udf_next_aext(inode, &epos, &eloc, &elen, &etype, 1)) {
 		udf_write_aext(inode, &oepos, &eloc, (etype << 30) | elen, 1);
 		if (oepos.bh != epos.bh) {
 			oepos.block = epos.block;
@@ -2353,14 +2366,19 @@ int8_t udf_delete_aext(struct inode *inode, struct extent_position epos)
 	return (elen >> 30);
 }
 
-int8_t inode_bmap(struct inode *inode, sector_t block,
-		  struct extent_position *pos, struct kernel_lb_addr *eloc,
-		  uint32_t *elen, sector_t *offset)
+/*
+ * return 0 when iudf_next_aext() loop success.
+ * return err < 0 and err != -ENODATA indicates error.
+ * return err == -ENODATA indicates hit EOF.
+ */
+int inode_bmap(struct inode *inode, sector_t block, struct extent_position *pos,
+	       struct kernel_lb_addr *eloc, uint32_t *elen, sector_t *offset,
+	       int8_t *etype)
 {
 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
 	loff_t lbcount = 0, bcount = (loff_t) block << blocksize_bits;
-	int8_t etype;
 	struct udf_inode_info *iinfo;
+	int err = 0;
 
 	iinfo = UDF_I(inode);
 	if (!udf_read_extent_cache(inode, bcount, &lbcount, pos)) {
@@ -2370,11 +2388,11 @@ int8_t inode_bmap(struct inode *inode, sector_t block,
 	}
 	*elen = 0;
 	do {
-		etype = udf_next_aext(inode, pos, eloc, elen, 1);
-		if (etype == -1) {
+		err = udf_next_aext(inode, pos, eloc, elen, etype, 1);
+		if (err < 0) {
 			*offset = (bcount - lbcount) >> blocksize_bits;
 			iinfo->i_lenExtents = lbcount;
-			return -1;
+			return err;
 		}
 		lbcount += *elen;
 	} while (lbcount <= bcount);
@@ -2382,5 +2400,5 @@ int8_t inode_bmap(struct inode *inode, sector_t block,
 	udf_update_extent_cache(inode, lbcount - *elen, pos);
 	*offset = (bcount + *elen - lbcount) >> blocksize_bits;
 
-	return etype;
+	return 0;
 }
diff --git a/fs/udf/partition.c b/fs/udf/partition.c
index af877991edc1..c441d4ae1f96 100644
--- a/fs/udf/partition.c
+++ b/fs/udf/partition.c
@@ -282,9 +282,11 @@ static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block,
 	sector_t ext_offset;
 	struct extent_position epos = {};
 	uint32_t phyblock;
+	int8_t etype;
+	int err = 0;
 
-	if (inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset) !=
-						(EXT_RECORDED_ALLOCATED >> 30))
+	err = inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset, &etype);
+	if (err || etype != (EXT_RECORDED_ALLOCATED >> 30))
 		phyblock = 0xFFFFFFFF;
 	else {
 		map = &UDF_SB(sb)->s_partmaps[partition];
diff --git a/fs/udf/super.c b/fs/udf/super.c
index 3460ecc826d1..8c34224e1aee 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -2482,13 +2482,14 @@ static unsigned int udf_count_free_table(struct super_block *sb,
 	uint32_t elen;
 	struct kernel_lb_addr eloc;
 	struct extent_position epos;
+	int8_t etype;
 
 	mutex_lock(&UDF_SB(sb)->s_alloc_mutex);
 	epos.block = UDF_I(table)->i_location;
 	epos.offset = sizeof(struct unallocSpaceEntry);
 	epos.bh = NULL;
 
-	while (udf_next_aext(table, &epos, &eloc, &elen, 1) != -1)
+	while (!udf_next_aext(table, &epos, &eloc, &elen, &etype, 1))
 		accum += (elen >> table->i_sb->s_blocksize_bits);
 
 	brelse(epos.bh);
diff --git a/fs/udf/truncate.c b/fs/udf/truncate.c
index a686c10fd709..a70b6ae4ab8a 100644
--- a/fs/udf/truncate.c
+++ b/fs/udf/truncate.c
@@ -85,7 +85,7 @@ void udf_truncate_tail_extent(struct inode *inode)
 		BUG();
 
 	/* Find the last extent in the file */
-	while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
+	while (!udf_next_aext(inode, &epos, &eloc, &elen, &netype, 1)) {
 		etype = netype;
 		lbcount += elen;
 		if (lbcount > inode->i_size) {
@@ -101,7 +101,7 @@ void udf_truncate_tail_extent(struct inode *inode)
 			epos.offset -= adsize;
 			extent_trunc(inode, &epos, &eloc, etype, elen, nelen);
 			epos.offset += adsize;
-			if (udf_next_aext(inode, &epos, &eloc, &elen, 1) != -1)
+			if (!udf_next_aext(inode, &epos, &eloc, &elen, &netype, 1))
 				udf_err(inode->i_sb,
 					"Extent after EOF in inode %u\n",
 					(unsigned)inode->i_ino);
@@ -132,13 +132,13 @@ void udf_discard_prealloc(struct inode *inode)
 	epos.block = iinfo->i_location;
 
 	/* Find the last extent in the file */
-	while (udf_next_aext(inode, &epos, &eloc, &elen, 0) != -1) {
+	while (!udf_next_aext(inode, &epos, &eloc, &elen, &etype, 0)) {
 		brelse(prev_epos.bh);
 		prev_epos = epos;
 		if (prev_epos.bh)
 			get_bh(prev_epos.bh);
 
-		etype = udf_next_aext(inode, &epos, &eloc, &elen, 1);
+		udf_next_aext(inode, &epos, &eloc, &elen, &etype, 1);
 		lbcount += elen;
 	}
 	if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
@@ -188,6 +188,7 @@ int udf_truncate_extents(struct inode *inode)
 	loff_t byte_offset;
 	int adsize;
 	struct udf_inode_info *iinfo = UDF_I(inode);
+	int err = 0;
 
 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
 		adsize = sizeof(struct short_ad);
@@ -196,10 +197,10 @@ int udf_truncate_extents(struct inode *inode)
 	else
 		BUG();
 
-	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
+	err = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset, &etype);
 	byte_offset = (offset << sb->s_blocksize_bits) +
 		(inode->i_size & (sb->s_blocksize - 1));
-	if (etype == -1) {
+	if (err < 0) {
 		/* We should extend the file? */
 		WARN_ON(byte_offset);
 		return 0;
@@ -217,8 +218,7 @@ int udf_truncate_extents(struct inode *inode)
 	else
 		lenalloc -= sizeof(struct allocExtDesc);
 
-	while ((etype = udf_current_aext(inode, &epos, &eloc,
-					 &elen, 0)) != -1) {
+	while (!udf_current_aext(inode, &epos, &eloc, &elen, &etype, 0)) {
 		if (etype == (EXT_NEXT_EXTENT_ALLOCDESCS >> 30)) {
 			udf_write_aext(inode, &epos, &neloc, nelen, 0);
 			if (indirect_ext_len) {
diff --git a/fs/udf/udfdecl.h b/fs/udf/udfdecl.h
index 88692512a466..c9b1956157d3 100644
--- a/fs/udf/udfdecl.h
+++ b/fs/udf/udfdecl.h
@@ -157,8 +157,8 @@ extern struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
 extern int udf_setsize(struct inode *, loff_t);
 extern void udf_evict_inode(struct inode *);
 extern int udf_write_inode(struct inode *, struct writeback_control *wbc);
-extern int8_t inode_bmap(struct inode *, sector_t, struct extent_position *,
-			 struct kernel_lb_addr *, uint32_t *, sector_t *);
+extern int inode_bmap(struct inode *, sector_t, struct extent_position *,
+		      struct kernel_lb_addr *, uint32_t *, sector_t *, int8_t *);
 int udf_get_block(struct inode *, sector_t, struct buffer_head *, int);
 extern int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
 				   struct extent_position *epos);
@@ -169,10 +169,10 @@ extern int udf_add_aext(struct inode *, struct extent_position *,
 extern void udf_write_aext(struct inode *, struct extent_position *,
 			   struct kernel_lb_addr *, uint32_t, int);
 extern int8_t udf_delete_aext(struct inode *, struct extent_position);
-extern int8_t udf_next_aext(struct inode *, struct extent_position *,
-			    struct kernel_lb_addr *, uint32_t *, int);
-extern int8_t udf_current_aext(struct inode *, struct extent_position *,
-			       struct kernel_lb_addr *, uint32_t *, int);
+extern int udf_next_aext(struct inode *, struct extent_position *,
+			 struct kernel_lb_addr *, uint32_t *, int8_t *, int);
+extern int udf_current_aext(struct inode *, struct extent_position *,
+			    struct kernel_lb_addr *, uint32_t *, int8_t *, int);
 extern void udf_update_extra_perms(struct inode *inode, umode_t mode);
 
 /* misc.c */