[[PATCH for v6]] KVM: SEV: fix snp_launch_finish

From: Harald Hoyer
Date: Thu Sep 08 2022 - 10:56:13 EST


The `params.auth_key_en` indicator does _not_ specify, whether an
ID_AUTH struct should be sent or not, but, wheter the ID_AUTH struct
contains an author key or not. The firmware always expects an ID_AUTH block.

Link: https://lore.kernel.org/all/cover.1655761627.git.ashish.kalra@xxxxxxx/
Signed-off-by: Harald Hoyer <harald@xxxxxxxxxxx>
---
arch/x86/kvm/svm/sev.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 85357dc4d231..5cf4be6a33ba 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -2242,17 +2242,18 @@ static int snp_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)

data->id_block_en = 1;
data->id_block_paddr = __sme_pa(id_block);
- }

- if (params.auth_key_en) {
id_auth = psp_copy_user_blob(params.id_auth_uaddr, KVM_SEV_SNP_ID_AUTH_SIZE);
if (IS_ERR(id_auth)) {
ret = PTR_ERR(id_auth);
goto e_free_id_block;
}

- data->auth_key_en = 1;
data->id_auth_paddr = __sme_pa(id_auth);
+
+ if (params.auth_key_en) {
+ data->auth_key_en = 1;
+ }
}

data->gctx_paddr = __psp_pa(sev->snp_context);
--
2.37.1