kernel: mm/filemap: skip to create PMD-sized page cache if needed

A vulnerability was found in the Linux kernel related to how large page caching is handled, particularly for AMD64 architectures. The issue stems from the xarray data structure's inability to support PMD-sized page caches when the base page size is larger than MAXPAGECACHEORDER. The particular...

kernel: mm/filemap: make MAX_PAGECACHE_ORDER acceptable to xarray

In the Linux kernel, the following vulnerability has been resolved: mm/filemap: make MAXPAGECACHEORDER acceptable to xarray Patch series "mm/filemap: Limit page cache size to that supported by xarray", v2. Currently, xarray can't support arbitrary page cache size. More details can be found from t...

CVE-2024-42317

The CVE-2024-42317 issue affects the Linux kernel mm/huge_memory path on ARM64 with 64KB base pages. It stems from xarray not supporting arbitrary page cache sizes beyond MAX_PAGECACHE_ORDER, which can allow a 512 MB page cache in the collapsing path and triggers a warning when splitting an xarra...