CVE-2025-68728

In the Linux kernel, the following vulnerability has been resolved:

ntfs3: fix uninit memory after failed mi_read in mi_format_new

Fix a KMSAN un-init bug found by syzkaller.

ntfs_get_bh() expects a buffer from sb_getblk(), that buffer may not be
uptodate. We do not bring the buffer uptodate before setting it as
uptodate. If the buffer were to not be uptodate, it could mean adding a
buffer with un-init data to the mi record. Attempting to load that record
will trigger KMSAN.

Avoid this by setting the buffer as uptodate, if its not already, by
overwriting it.