| Message ID | 20210607061532.27459-1-Ashish.Kalra@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: SVM: Fix SEV SEND_START session length & SEND_UPDATE_DATA query length after commit 238eca821cee | expand |
On 07/06/21 08:15, Ashish Kalra wrote: > From: Ashish Kalra <ashish.kalra@amd.com> > > Commit 238eca821cee ("KVM: SVM: Allocate SEV command structures on local stack") > uses the local stack to allocate the structures used to communicate with the PSP, > which were earlier being kzalloced. This breaks SEV live migration for > computing the SEND_START session length and SEND_UPDATE_DATA query length as > session_len and trans_len and hdr_len fields are not zeroed respectively for > the above commands before issuing the SEV Firmware API call, hence the > firmware returns incorrect session length and update data header or trans length. > > Also the SEV Firmware API returns SEV_RET_INVALID_LEN firmware error > for these length query API calls, and the return value and the > firmware error needs to be passed to the userspace as it is, so > need to remove the return check in the KVM code. > > Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> > --- > arch/x86/kvm/svm/sev.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 5bc887e9a986..e0ce5da97fc2 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -1103,10 +1103,9 @@ __sev_send_start_query_session_length(struct kvm *kvm, struct kvm_sev_cmd *argp, > struct sev_data_send_start data; > int ret; > > + memset(&data, 0, sizeof(data)); > data.handle = sev->handle; > ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); > - if (ret < 0) > - return ret; > > params->session_len = data.session_len; > if (copy_to_user((void __user *)(uintptr_t)argp->data, params, > @@ -1215,10 +1214,9 @@ __sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp, > struct sev_data_send_update_data data; > int ret; > > + memset(&data, 0, sizeof(data)); > data.handle = sev->handle; > ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); > - if (ret < 0) > - return ret; > > params->hdr_len = data.hdr_len; > params->trans_len = data.trans_len; > Queued, thanks. Paolo
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 5bc887e9a986..e0ce5da97fc2 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1103,10 +1103,9 @@ __sev_send_start_query_session_length(struct kvm *kvm, struct kvm_sev_cmd *argp, struct sev_data_send_start data; int ret; + memset(&data, 0, sizeof(data)); data.handle = sev->handle; ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); - if (ret < 0) - return ret; params->session_len = data.session_len; if (copy_to_user((void __user *)(uintptr_t)argp->data, params, @@ -1215,10 +1214,9 @@ __sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp, struct sev_data_send_update_data data; int ret; + memset(&data, 0, sizeof(data)); data.handle = sev->handle; ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); - if (ret < 0) - return ret; params->hdr_len = data.hdr_len; params->trans_len = data.trans_len;