In the Linux kernel, the following vulnerability has been resolved: dax/fsdev: clear...

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

dax/fsdev: clear vmemmap_shift when binding static pgmap

Clear pgmap->vmemmap_shift for static DAX devices. When rebinding a static device from device_dax (which may set vmemmap_shift based on alignment) to fsdev_dax, the stale vmemmap_shift persists on the shared pgmap. Explicitly zero it before devm_memremap_pages() so the vmemmap is built for order-0 folios as fsdev requires.