arm64/mm: Validate hotplug range before creating linear mapping
During memory hotplug process, the linear mapping should not be created for a given memory range if that would fall outside the maximum allowed linear range. Else it might cause memory corruption in the kernel virtual space. Maximum linear mapping region is [PAGE_OFFSET..(PAGE_END -1)] accommodating both its ends but excluding PAGE_END. Max physical range that can be mapped inside this linear mapping range, must also be derived from its end points. This ensures that arch_add_memory() validates memory hot add range for its potential linear mapping requirements, before creating it with __create_pgd_mapping(). Fixes: 4ab21506 ("arm64: Add memory hotplug support") Signed-off-by:Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by:
Ard Biesheuvel <ardb@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Steven Price <steven.price@arm.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Link: https://lore.kernel.org/r/1605252614-761-1-git-send-email-anshuman.khandual@arm.com Signed-off-by:
Will Deacon <will@kernel.org>
parent
04e613de
Please register or sign in to comment