git diff fs/ext2fs/ext2_alloc.c
diff --git a/fs/ext2fs/ext2_alloc.c b/fs/ext2fs/ext2_alloc.c
index 4c265a1a8..9e05d02de 100644
--- a/fs/ext2fs/ext2_alloc.c
+++ b/fs/ext2fs/ext2_alloc.c
@@ -1067,7 +1067,7 @@ ext2_alloccg(struct inode *ip, int cg, daddr_t bpref, int size)
                start = dtogd(fs, bpref) / NBBY;
        else
                start = 0;
-       end = howmany(fs->e2fs_fpg, NBBY) - start;
+       end = howmany(fs->e2fs_fpg, NBBY);
 retry:
        runlen = 0;
        runstart = 0;

The variable "start" is the starting position where we traverse the block bitmap of a cylinder group , and the variable "end" is the ending position. Therefore, we shouldn't subtract "start" in the process of calculating "end".