KVM: arm/arm64: Check pagesize when allocating a hugepage at Stage 2

KVM only supports PMD hugepages at stage 2 but doesn't actually check
that the provided hugepage memory pagesize is PMD_SIZE before populating
stage 2 entries.

In cases where the backing hugepage size is smaller than PMD_SIZE (such
as when using contiguous hugepages), KVM can end up creating stage 2
mappings that extend beyond the supplied memory.

Fix this by checking for the pagesize of userspace vma before creating
PMD hugepage at stage 2.

Fixes: 66b3923a1a0f77a ("arm64: hugetlb: add support for PTE contiguous bit")
Signed-off-by: Punit Agrawal <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: <[email protected]> # v4.5+
Reviewed-by: Christoffer Dall <[email protected]>
Signed-off-by: Christoffer Dall <[email protected]>

0 files changed, 0 insertions, 0 deletions