From 68e9c254f662e4c2763e672b026a513d91f3a1c4 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 24 Jan 2017 11:56:21 +0100 Subject: kvm: fix page struct leak in handle_vmon [ Upstream commit 06ce521af9558814b8606c0476c54497cf83a653 ] handle_vmon gets a reference on VMXON region page, but does not release it. Release the reference. Found by syzkaller; based on a patch by Dmitry. Reported-by: Dmitry Vyukov Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin --- arch/x86/kvm/vmx.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 048830f2927d..f5c6f74f85a3 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6527,14 +6527,20 @@ static int nested_vmx_check_vmptr(struct kvm_vcpu *vcpu, int exit_reason, } page = nested_get_page(vcpu, vmptr); - if (page == NULL || - *(u32 *)kmap(page) != VMCS12_REVISION) { + if (page == NULL) { nested_vmx_failInvalid(vcpu); + skip_emulated_instruction(vcpu); + return 1; + } + if (*(u32 *)kmap(page) != VMCS12_REVISION) { kunmap(page); + nested_release_page_clean(page); + nested_vmx_failInvalid(vcpu); skip_emulated_instruction(vcpu); return 1; } kunmap(page); + nested_release_page_clean(page); vmx->nested.vmxon_ptr = vmptr; break; case EXIT_REASON_VMCLEAR: -- cgit v1.2.3