1 files changed, 55 insertions, 34 deletions

diff --git a/fs/udf/super.c b/fs/udf/super.c
index 36661acaf..4942549e7 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -78,6 +78,15 @@
 #define VSD_FIRST_SECTOR_OFFSET		32768
 #define VSD_MAX_SECTOR_OFFSET		0x800000
 
+/*
+ * Maximum number of Terminating Descriptor / Logical Volume Integrity
+ * Descriptor redirections. The chosen numbers are arbitrary - just that we
+ * hopefully don't limit any real use of rewritten inode on write-once media
+ * but avoid looping for too long on corrupted media.
+ */
+#define UDF_MAX_TD_NESTING 64
+#define UDF_MAX_LVID_NESTING 1000
+
 enum { UDF_MAX_LINKS = 0xffff };
 
 /* These are the "meat" - everything else is stuffing */
@@ -942,13 +951,13 @@ out2:
 }
 
 struct inode *udf_find_metadata_inode_efe(struct super_block *sb,
-					u32 meta_file_loc, u32 partition_num)
+					u32 meta_file_loc, u32 partition_ref)
 {
 	struct kernel_lb_addr addr;
 	struct inode *metadata_fe;
 
 	addr.logicalBlockNum = meta_file_loc;
-	addr.partitionReferenceNum = partition_num;
+	addr.partitionReferenceNum = partition_ref;
 
 	metadata_fe = udf_iget_special(sb, &addr);
 
@@ -965,7 +974,8 @@ struct inode *udf_find_metadata_inode_efe(struct super_block *sb,
 	return metadata_fe;
 }
 
-static int udf_load_metadata_files(struct super_block *sb, int partition)
+static int udf_load_metadata_files(struct super_block *sb, int partition,
+				   int type1_index)
 {
 	struct udf_sb_info *sbi = UDF_SB(sb);
 	struct udf_part_map *map;
@@ -975,20 +985,21 @@ static int udf_load_metadata_files(struct super_block *sb, int partition)
 
 	map = &sbi->s_partmaps[partition];
 	mdata = &map->s_type_specific.s_metadata;
+	mdata->s_phys_partition_ref = type1_index;
 
 	/* metadata address */
 	udf_debug("Metadata file location: block = %d part = %d\n",
-		  mdata->s_meta_file_loc, map->s_partition_num);
+		  mdata->s_meta_file_loc, mdata->s_phys_partition_ref);
 
 	fe = udf_find_metadata_inode_efe(sb, mdata->s_meta_file_loc,
-					 map->s_partition_num);
+					 mdata->s_phys_partition_ref);
 	if (IS_ERR(fe)) {
 		/* mirror file entry */
 		udf_debug("Mirror metadata file location: block = %d part = %d\n",
-			  mdata->s_mirror_file_loc, map->s_partition_num);
+			  mdata->s_mirror_file_loc, mdata->s_phys_partition_ref);
 
 		fe = udf_find_metadata_inode_efe(sb, mdata->s_mirror_file_loc,
-						 map->s_partition_num);
+						 mdata->s_phys_partition_ref);
 
 		if (IS_ERR(fe)) {
 			udf_err(sb, "Both metadata and mirror metadata inode efe can not found\n");
@@ -1006,7 +1017,7 @@ static int udf_load_metadata_files(struct super_block *sb, int partition)
 	*/
 	if (mdata->s_bitmap_file_loc != 0xFFFFFFFF) {
 		addr.logicalBlockNum = mdata->s_bitmap_file_loc;
-		addr.partitionReferenceNum = map->s_partition_num;
+		addr.partitionReferenceNum = mdata->s_phys_partition_ref;
 
 		udf_debug("Bitmap file location: block = %d part = %d\n",
 			  addr.logicalBlockNum, addr.partitionReferenceNum);
@@ -1274,7 +1285,7 @@ static int udf_load_partdesc(struct super_block *sb, sector_t block)
 	p = (struct partitionDesc *)bh->b_data;
 	partitionNumber = le16_to_cpu(p->partitionNumber);
 
-	/* First scan for TYPE1, SPARABLE and METADATA partitions */
+	/* First scan for TYPE1 and SPARABLE partitions */
 	for (i = 0; i < sbi->s_partitions; i++) {
 		map = &sbi->s_partmaps[i];
 		udf_debug("Searching map: (%d == %d)\n",
@@ -1324,7 +1335,7 @@ static int udf_load_partdesc(struct super_block *sb, sector_t block)
 		goto out_bh;
 
 	if (map->s_partition_type == UDF_METADATA_MAP25) {
-		ret = udf_load_metadata_files(sb, i);
+		ret = udf_load_metadata_files(sb, i, type1_idx);
 		if (ret < 0) {
 			udf_err(sb, "error loading MetaData partition map %d\n",
 				i);
@@ -1541,42 +1552,52 @@ out_bh:
 }
 
 /*
- * udf_load_logicalvolint
- *
+ * Find the prevailing Logical Volume Integrity Descriptor.
  */
 static void udf_load_logicalvolint(struct super_block *sb, struct kernel_extent_ad loc)
 {
-	struct buffer_head *bh = NULL;
+	struct buffer_head *bh, *final_bh;
 	uint16_t ident;
 	struct udf_sb_info *sbi = UDF_SB(sb);
 	struct logicalVolIntegrityDesc *lvid;
+	int indirections = 0;
+
+	while (++indirections <= UDF_MAX_LVID_NESTING) {
+		final_bh = NULL;
+		while (loc.extLength > 0 &&
+			(bh = udf_read_tagged(sb, loc.extLocation,
+					loc.extLocation, &ident))) {
+			if (ident != TAG_IDENT_LVID) {
+				brelse(bh);
+				break;
+			}
+
+			brelse(final_bh);
+			final_bh = bh;
 
-	while (loc.extLength > 0 &&
-	       (bh = udf_read_tagged(sb, loc.extLocation,
-				     loc.extLocation, &ident)) &&
-	       ident == TAG_IDENT_LVID) {
-		sbi->s_lvid_bh = bh;
-		lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
+			loc.extLength -= sb->s_blocksize;
+			loc.extLocation++;
+		}
 
-		if (lvid->nextIntegrityExt.extLength)
-			udf_load_logicalvolint(sb,
-				leea_to_cpu(lvid->nextIntegrityExt));
+		if (!final_bh)
+			return;
 
-		if (sbi->s_lvid_bh != bh)
-			brelse(bh);
-		loc.extLength -= sb->s_blocksize;
-		loc.extLocation++;
+		brelse(sbi->s_lvid_bh);
+		sbi->s_lvid_bh = final_bh;
+
+		lvid = (struct logicalVolIntegrityDesc *)final_bh->b_data;
+		if (lvid->nextIntegrityExt.extLength == 0)
+			return;
+
+		loc = leea_to_cpu(lvid->nextIntegrityExt);
 	}
-	if (sbi->s_lvid_bh != bh)
-		brelse(bh);
+
+	udf_warn(sb, "Too many LVID indirections (max %u), ignoring.\n",
+		UDF_MAX_LVID_NESTING);
+	brelse(sbi->s_lvid_bh);
+	sbi->s_lvid_bh = NULL;
 }
 
-/*
- * Maximum number of Terminating Descriptor redirections. The chosen number is
- * arbitrary - just that we hopefully don't limit any real use of rewritten
- * inode on write-once media but avoid looping for too long on corrupted media.
- */
-#define UDF_MAX_TD_NESTING 64
 
 /*
  * Process a main/reserve volume descriptor sequence.