From: Sean Christopherson Date: Tue, 20 Dec 2022 15:34:27 +0000 (+0000) Subject: KVM: x86: Sanity check inputs to kvm_handle_memory_failure() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=77b1908e10eccf34310ffd95b0b455c01aa76286;p=linux.git KVM: x86: Sanity check inputs to kvm_handle_memory_failure() Add a sanity check in kvm_handle_memory_failure() to assert that a valid x86_exception structure is provided if the memory "failure" wants to propagate a fault into the guest. If a memory failure happens during a direct guest physical memory access, e.g. for nested VMX, KVM hardcodes the failure to X86EMUL_IO_NEEDED and doesn't provide an exception pointer (because the exception struct would just be filled with garbage). Signed-off-by: Sean Christopherson Message-Id: <20221220153427.514032-1-seanjc@google.com> Signed-off-by: Paolo Bonzini --- diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index fd6c01a393128..5c3ce39cdccbf 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -13132,6 +13132,9 @@ int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r, struct x86_exception *e) { if (r == X86EMUL_PROPAGATE_FAULT) { + if (KVM_BUG_ON(!e, vcpu->kvm)) + return -EIO; + kvm_inject_emulated_page_fault(vcpu, e); return 1; }