From e4e11cc0f81ee7be17d6f6fb96128a6d51c0e838 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Wed, 17 Oct 2018 20:21:16 +0200 Subject: KVM: arm64: Safety check PSTATE when entering guest and handle IL This commit adds a paranoid check when entering the guest to make sure we don't attempt running guest code in an equally or more privilged mode than the hypervisor. We also catch other accidental programming of the SPSR_EL2 which results in an illegal exception return and report this safely back to the user. Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/kvm/handle_exit.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'arch/arm64/kvm/handle_exit.c') diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index e5e741bfffe1..35a81bebd02b 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -284,6 +284,13 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, */ run->exit_reason = KVM_EXIT_FAIL_ENTRY; return 0; + case ARM_EXCEPTION_IL: + /* + * We attempted an illegal exception return. Guest state must + * have been corrupted somehow. Give up. + */ + run->exit_reason = KVM_EXIT_FAIL_ENTRY; + return -EINVAL; default: kvm_pr_unimpl("Unsupported exception type: %d", exception_index); -- cgit v1.2.3