mm: use aligned address in copy_user_gigantic_page()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: mm: use aligned address in copy_user_gigantic_page() In current kernel, hugetlb_wp() calls copy_user_large_folio() with the fault address. Where the fault address may be not aligned with the huge page size. Then, copy_user_large_folio() may call copy_user_gigantic_page() with the address, while copy_user_gigantic_page() requires the address to be huge page size aligned. So, this may cause memory corruption or information leak, addtional, use more obvious naming 'addr_hint' instead of 'addr' for copy_user_gigantic_page().

References

• https://git.kernel.org/stable/c/cb12d61361ce769672c7c7bd32107252598cdd8b
• https://git.kernel.org/stable/c/f5d09de9f1bf9674c6418ff10d0a40cfe29268e1