[PATCH -tip] KVM: SVM: nested: Initialize on-stack pointers in svm_set_nested_state()

From: Joerg Roedel
Date: Mon Sep 14 2020 - 08:13:21 EST


From: Joerg Roedel <jroedel@xxxxxxx>

The save and ctl pointers need to be initialized to NULL because there
is a way through the function in which there is no memory allocated
for the pointers but where they are freed in the end.

This involves the 'goto out_set_gif' before the memory for the
pointers is allocated.

Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Fixes: 6ccbd29ade0d ("KVM: SVM: nested: Don't allocate VMCB structures on stack")
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
arch/x86/kvm/svm/nested.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 598a769f1961..72a3d6f87107 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1062,8 +1062,8 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
struct vmcb *hsave = svm->nested.hsave;
struct vmcb __user *user_vmcb = (struct vmcb __user *)
&user_kvm_nested_state->data.svm[0];
- struct vmcb_control_area *ctl;
- struct vmcb_save_area *save;
+ struct vmcb_control_area *ctl = NULL;
+ struct vmcb_save_area *save = NULL;
int ret;
u32 cr0;

--
2.28.0