diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index d47a80e..21ee30b 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4860,7 +4860,7 @@
 		if (len >= EXT4_BLOCKS_PER_GROUP(sb))
 			len -= (EXT4_BLOCKS_PER_GROUP(sb) - first_block);
 		else
-			last_block = len;
+			last_block = first_block + len;
 
 		if (e4b.bd_info->bb_free >= minlen) {
 			cnt = ext4_trim_all_free(sb, &e4b, first_block,