diff --git a/fs/udf/super.c b/fs/udf/super.c
index f73239a..5c5d5fd 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1658,7 +1658,7 @@ static noinline int udf_process_sequence(
 				next_e = le32_to_cpu(
 					vdp->nextVolDescSeqExt.extLength);
 				next_e = next_e >> sb->s_blocksize_bits;
-				next_e += next_s;
+				next_e += next_s - 1;
 			}
 			break;
 		case TAG_IDENT_IUVD: /* ISO 13346 3/10.4 */
@@ -1760,13 +1760,13 @@ static int udf_load_sequence(struct super_block *sb, struct buffer_head *bh,
 	main_s = le32_to_cpu(anchor->mainVolDescSeqExt.extLocation);
 	main_e = le32_to_cpu(anchor->mainVolDescSeqExt.extLength);
 	main_e = main_e >> sb->s_blocksize_bits;
-	main_e += main_s;
+	main_e += main_s - 1;
 
 	/* Locate the reserve sequence */
 	reserve_s = le32_to_cpu(anchor->reserveVolDescSeqExt.extLocation);
 	reserve_e = le32_to_cpu(anchor->reserveVolDescSeqExt.extLength);
 	reserve_e = reserve_e >> sb->s_blocksize_bits;
-	reserve_e += reserve_s;
+	reserve_e += reserve_s - 1;
 
 	/* Process the main & reserve sequences */
 	/* responsible for finding the PartitionDesc(s) */