diff options
Diffstat (limited to 'drivers/virt/coco/sev-guest/sev-guest.c')
| -rw-r--r-- | drivers/virt/coco/sev-guest/sev-guest.c | 58 |
1 files changed, 43 insertions, 15 deletions
diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c index 264b6523fe52..70fbc9a3e703 100644 --- a/drivers/virt/coco/sev-guest/sev-guest.c +++ b/drivers/virt/coco/sev-guest/sev-guest.c @@ -38,12 +38,6 @@ struct snp_guest_dev { struct miscdevice misc; struct snp_msg_desc *msg_desc; - - union { - struct snp_report_req report; - struct snp_derived_key_req derived_key; - struct snp_ext_report_req ext_report; - } req; }; /* @@ -71,7 +65,7 @@ struct snp_req_resp { static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_ioctl *arg) { - struct snp_report_req *report_req = &snp_dev->req.report; + struct snp_report_req *report_req __free(kfree) = NULL; struct snp_msg_desc *mdesc = snp_dev->msg_desc; struct snp_report_resp *report_resp; struct snp_guest_req req = {}; @@ -80,6 +74,10 @@ static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_io if (!arg->req_data || !arg->resp_data) return -EINVAL; + report_req = kzalloc(sizeof(*report_req), GFP_KERNEL_ACCOUNT); + if (!report_req) + return -ENOMEM; + if (copy_from_user(report_req, (void __user *)arg->req_data, sizeof(*report_req))) return -EFAULT; @@ -116,7 +114,7 @@ e_free: static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_request_ioctl *arg) { - struct snp_derived_key_req *derived_key_req = &snp_dev->req.derived_key; + struct snp_derived_key_req *derived_key_req __free(kfree) = NULL; struct snp_derived_key_resp derived_key_resp = {0}; struct snp_msg_desc *mdesc = snp_dev->msg_desc; struct snp_guest_req req = {}; @@ -136,6 +134,10 @@ static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_reque if (sizeof(buf) < resp_len) return -ENOMEM; + derived_key_req = kzalloc(sizeof(*derived_key_req), GFP_KERNEL_ACCOUNT); + if (!derived_key_req) + return -ENOMEM; + if (copy_from_user(derived_key_req, (void __user *)arg->req_data, sizeof(*derived_key_req))) return -EFAULT; @@ -168,16 +170,21 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques struct snp_req_resp *io) { - struct snp_ext_report_req *report_req = &snp_dev->req.ext_report; + struct snp_ext_report_req *report_req __free(kfree) = NULL; struct snp_msg_desc *mdesc = snp_dev->msg_desc; struct snp_report_resp *report_resp; struct snp_guest_req req = {}; int ret, npages = 0, resp_len; sockptr_t certs_address; + struct page *page; if (sockptr_is_null(io->req_data) || sockptr_is_null(io->resp_data)) return -EINVAL; + report_req = kzalloc(sizeof(*report_req), GFP_KERNEL_ACCOUNT); + if (!report_req) + return -ENOMEM; + if (copy_from_sockptr(report_req, io->req_data, sizeof(*report_req))) return -EFAULT; @@ -203,8 +210,20 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques * the host. If host does not supply any certs in it, then copy * zeros to indicate that certificate data was not provided. */ - memset(mdesc->certs_data, 0, report_req->certs_len); npages = report_req->certs_len >> PAGE_SHIFT; + page = alloc_pages(GFP_KERNEL_ACCOUNT | __GFP_ZERO, + get_order(report_req->certs_len)); + if (!page) + return -ENOMEM; + + req.certs_data = page_address(page); + ret = set_memory_decrypted((unsigned long)req.certs_data, npages); + if (ret) { + pr_err("failed to mark page shared, ret=%d\n", ret); + __free_pages(page, get_order(report_req->certs_len)); + return -EFAULT; + } + cmd: /* * The intermediate response buffer is used while decrypting the @@ -213,10 +232,12 @@ cmd: */ resp_len = sizeof(report_resp->data) + mdesc->ctx->authsize; report_resp = kzalloc(resp_len, GFP_KERNEL_ACCOUNT); - if (!report_resp) - return -ENOMEM; + if (!report_resp) { + ret = -ENOMEM; + goto e_free_data; + } - mdesc->input.data_npages = npages; + req.input.data_npages = npages; req.msg_version = arg->msg_version; req.msg_type = SNP_MSG_REPORT_REQ; @@ -231,7 +252,7 @@ cmd: /* If certs length is invalid then copy the returned length */ if (arg->vmm_error == SNP_GUEST_VMM_ERR_INVALID_LEN) { - report_req->certs_len = mdesc->input.data_npages << PAGE_SHIFT; + report_req->certs_len = req.input.data_npages << PAGE_SHIFT; if (copy_to_sockptr(io->req_data, report_req, sizeof(*report_req))) ret = -EFAULT; @@ -240,7 +261,7 @@ cmd: if (ret) goto e_free; - if (npages && copy_to_sockptr(certs_address, mdesc->certs_data, report_req->certs_len)) { + if (npages && copy_to_sockptr(certs_address, req.certs_data, report_req->certs_len)) { ret = -EFAULT; goto e_free; } @@ -250,6 +271,13 @@ cmd: e_free: kfree(report_resp); +e_free_data: + if (npages) { + if (set_memory_encrypted((unsigned long)req.certs_data, npages)) + WARN_ONCE(ret, "failed to restore encryption mask (leak it)\n"); + else + __free_pages(page, get_order(report_req->certs_len)); + } return ret; } |