CVE-2024-49902

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

jfs: check if leafidx greater than num leaves per dmap tree

syzbot report a out of bounds in dbSplit, it because dmt_leafidx greater
than num leaves per dmap tree, add a checking for dmt_leafidx in dbFindLeaf.

Shaggy:
Modified sanity check to apply to control pages as well as leaf pages.