From 1871c6020d7308afb99127bba51f04548e7ca84e Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Wed, 10 Feb 2010 14:21:32 +0200 Subject: KVM: x86 emulator: fix memory access during x86 emulation Currently when x86 emulator needs to access memory, page walk is done with broadest permission possible, so if emulated instruction was executed by userspace process it can still access kernel memory. Fix that by providing correct memory access to page walker during emulation. Signed-off-by: Gleb Natapov Cc: stable@kernel.org Signed-off-by: Avi Kivity --- arch/x86/kvm/paging_tmpl.h | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'arch/x86/kvm/paging_tmpl.h') diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index df15a53..81eab9a 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -490,18 +490,23 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva) spin_unlock(&vcpu->kvm->mmu_lock); } -static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr) +static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr, u32 access, + u32 *error) { struct guest_walker walker; gpa_t gpa = UNMAPPED_GVA; int r; - r = FNAME(walk_addr)(&walker, vcpu, vaddr, 0, 0, 0); + r = FNAME(walk_addr)(&walker, vcpu, vaddr, + !!(access & PFERR_WRITE_MASK), + !!(access & PFERR_USER_MASK), + !!(access & PFERR_FETCH_MASK)); if (r) { gpa = gfn_to_gpa(walker.gfn); gpa |= vaddr & ~PAGE_MASK; - } + } else if (error) + *error = walker.error_code; return gpa; } -- cgit v1.1