From 9dfbc2f82ac82eb7398ae2d0c125a52e525edbc6 Mon Sep 17 00:00:00 2001 From: Santosh Shukla Date: Mon, 26 Oct 2020 16:54:07 +0530 Subject: [PATCH] KVM: arm64: Force PTE mapping on fault resulting in a device mapping [ Upstream commit 91a2c34b7d6fadc9c5d9433c620ea4c32ee7cae8 ] VFIO allows a device driver to resolve a fault by mapping a MMIO range. This can be subsequently result in user_mem_abort() to try and compute a huge mapping based on the MMIO pfn, which is a sure recipe for things to go wrong. Instead, force a PTE mapping when the pfn faulted in has a device mapping. Fixes: 6d674e28f642 ("KVM: arm/arm64: Properly handle faulting of device mappings") Suggested-by: Marc Zyngier Signed-off-by: Santosh Shukla [maz: rewritten commit message] Signed-off-by: Marc Zyngier Reviewed-by: Gavin Shan Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/1603711447-11998-2-git-send-email-sashukla@nvidia.com Signed-off-by: Sasha Levin --- virt/kvm/arm/mmu.c | 1 + 1 file changed, 1 insertion(+) diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index 8700402f3000..03a586ab6d27 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1756,6 +1756,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, if (kvm_is_device_pfn(pfn)) { mem_type = PAGE_S2_DEVICE; flags |= KVM_S2PTE_FLAG_IS_IOMAP; + force_pte = true; } else if (logging_active) { /* * Faults on pages in a memslot with logging enabled