From 26b471c7e2f7befd0f59c35b257749ca57e0ed70 Mon Sep 17 00:00:00 2001 From: Liran Alon Date: Sun, 16 Sep 2018 14:28:20 +0300 Subject: [PATCH] KVM: nVMX: Fix bad cleanup on error of get/set nested state IOCTLs The handlers of IOCTLs in kvm_arch_vcpu_ioctl() are expected to set their return value in "r" local var and break out of switch block when they encounter some error. This is because vcpu_load() is called before the switch block which have a proper cleanup of vcpu_put() afterwards. However, KVM_{GET,SET}_NESTED_STATE IOCTLs handlers just return immediately on error without performing above mentioned cleanup. Thus, change these handlers to behave as expected. Fixes: 8fcc4b5923af ("kvm: nVMX: Introduce KVM_CAP_NESTED_STATE") Reviewed-by: Mark Kanda Reviewed-by: Patrick Colp Signed-off-by: Liran Alon Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 4c39ec5fc4fe..edbf00ec56b3 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4010,19 +4010,23 @@ long kvm_arch_vcpu_ioctl(struct file *filp, break; BUILD_BUG_ON(sizeof(user_data_size) != sizeof(user_kvm_nested_state->size)); + r = -EFAULT; if (get_user(user_data_size, &user_kvm_nested_state->size)) - return -EFAULT; + break; r = kvm_x86_ops->get_nested_state(vcpu, user_kvm_nested_state, user_data_size); if (r < 0) - return r; + break; if (r > user_data_size) { if (put_user(r, &user_kvm_nested_state->size)) - return -EFAULT; - return -E2BIG; + r = -EFAULT; + else + r = -E2BIG; + break; } + r = 0; break; } @@ -4034,19 +4038,21 @@ long kvm_arch_vcpu_ioctl(struct file *filp, if (!kvm_x86_ops->set_nested_state) break; + r = -EFAULT; if (copy_from_user(&kvm_state, user_kvm_nested_state, sizeof(kvm_state))) - return -EFAULT; + break; + r = -EINVAL; if (kvm_state.size < sizeof(kvm_state)) - return -EINVAL; + break; if (kvm_state.flags & ~(KVM_STATE_NESTED_RUN_PENDING | KVM_STATE_NESTED_GUEST_MODE)) - return -EINVAL; + break; /* nested_run_pending implies guest_mode. */ if (kvm_state.flags == KVM_STATE_NESTED_RUN_PENDING) - return -EINVAL; + break; r = kvm_x86_ops->set_nested_state(vcpu, user_kvm_nested_state, &kvm_state); break; -- GitLab