[v7,1/4] KVM: x86: xen_hvm_config: cleanup return values

Commit Message

Maxim Levitsky Oct. 1, 2020, 11:29 a.m. UTC

Return 1 on errors that are caused by wrong guest behavior
(which will inject #GP to the guest)

And return a negative error value on issues that are
the kernel's fault (e.g -ENOMEM)

Signed-off-by: Maxim Levitsky <[e-mail]>
---
 arch/x86/kvm/x86.c | 23 +++++++++--------------
 1 file changed, 9 insertions(+), 14 deletions(-)

Patch

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c4015a43cc8a7..09a0cad49af51 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2812,24 +2812,19 @@  static int xen_hvm_config(struct kvm_vcpu *vcpu, u64 data)
 	u32 page_num = data & ~PAGE_MASK;
 	u64 page_addr = data & PAGE_MASK;
 	u8 *page;
-	int r;
 
-	r = -E2BIG;
 	if (page_num >= blob_size)
-		goto out;
-	r = -ENOMEM;
+		return 1;
+
 	page = memdup_user(blob_addr + (page_num * PAGE_SIZE), PAGE_SIZE);
-	if (IS_ERR(page)) {
-		r = PTR_ERR(page);
-		goto out;
+	if (IS_ERR(page))
+		return PTR_ERR(page);
+
+	if (kvm_vcpu_write_guest(vcpu, page_addr, page, PAGE_SIZE)) {
+		kfree(page);
+		return 1;
 	}
-	if (kvm_vcpu_write_guest(vcpu, page_addr, page, PAGE_SIZE))
-		goto out_free;
-	r = 0;
-out_free:
-	kfree(page);
-out:
-	return r;
+	return 0;
 }
 
 static inline bool kvm_pv_async_pf_enabled(struct kvm_vcpu *vcpu)