On Fri, Oct 06, 2017 at 08:06:05PM -0500, Brijesh Singh wrote:
> The SEV_PEK_CSR command can be used to generate a PEK certificate
> signing request. The command is defined in SEV spec section 5.7.
> 
> Cc: Paolo Bonzini <pbonz...@redhat.com>
> Cc: "Radim Krčmář" <rkrc...@redhat.com>
> Cc: Borislav Petkov <b...@suse.de>
> Cc: Herbert Xu <herb...@gondor.apana.org.au>
> Cc: Gary Hook <gary.h...@amd.com>
> Cc: Tom Lendacky <thomas.lenda...@amd.com>
> Cc: linux-crypto@vger.kernel.org
> Cc: k...@vger.kernel.org
> Cc: linux-ker...@vger.kernel.org
> Signed-off-by: Brijesh Singh <brijesh.si...@amd.com>
> ---
>  drivers/crypto/ccp/psp-dev.c | 85 
> ++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 85 insertions(+)

Ok, a couple of things here:

* Move the checks first and the allocations second so that you allocate
memory only after all checks have been passed and you don't allocate
pointlessly.

* That:

        if (state == SEV_STATE_WORKING) {
                ret = -EBUSY;
                goto e_free_blob;
        } else if (state == SEV_STATE_UNINIT) {
                ret = sev_firmware_init(&argp->error);
                if (ret)
                        goto e_free_blob;
                do_shutdown = 1;
        }

is a repeating pattern. Perhaps it should be called
sev_firmware_reinit() and called by other functions.

* The rest is simplifications and streamlining.

---
diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
index e3ee68afd068..d41f5448a25b 100644
--- a/drivers/crypto/ccp/psp-dev.c
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -302,33 +302,30 @@ static int sev_ioctl_pek_csr(struct sev_issue_cmd *argp)
        int ret, state;
        void *blob;
 
-       if (copy_from_user(&input, (void __user *)(uintptr_t)argp->data,
-                          sizeof(struct sev_user_data_pek_csr)))
+       if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
+               return -EFAULT;
+
+       if (!input.address)
+               return -EINVAL;
+
+       /* allocate a physically contiguous buffer to store the CSR blob */
+       if (!access_ok(VERIFY_WRITE, input.address, input.length) ||
+           input.length > SEV_FW_BLOB_MAX_SIZE)
                return -EFAULT;
 
        data = kzalloc(sizeof(*data), GFP_KERNEL);
        if (!data)
                return -ENOMEM;
 
-       /* allocate a temporary physical contigous buffer to store the CSR blob 
*/
-       blob = NULL;
-       if (input.address) {
-               if (!access_ok(VERIFY_WRITE, input.address, input.length) ||
-                   input.length > SEV_FW_BLOB_MAX_SIZE) {
-                       ret = -EFAULT;
-                       goto e_free;
-               }
-
-               blob = kmalloc(input.length, GFP_KERNEL);
-               if (!blob) {
-                       ret = -ENOMEM;
-                       goto e_free;
-               }
-
-               data->address = __psp_pa(blob);
-               data->len = input.length;
+       blob = kmalloc(input.length, GFP_KERNEL);
+       if (!blob) {
+               ret = -ENOMEM;
+               goto e_free;
        }
 
+       data->address = __psp_pa(blob);
+       data->len = input.length;
+
        ret = sev_platform_get_state(&state, &argp->error);
        if (ret)
                goto e_free_blob;
@@ -349,25 +346,23 @@ static int sev_ioctl_pek_csr(struct sev_issue_cmd *argp)
                do_shutdown = 1;
        }
 
-       ret = sev_handle_cmd(SEV_CMD_PEK_CSR, data, &argp->error);
+       ret = sev_do_cmd(SEV_CMD_PEK_CSR, data, &argp->error);
 
        input.length = data->len;
 
        /* copy blob to userspace */
-       if (blob &&
-           copy_to_user((void __user *)(uintptr_t)input.address,
-                       blob, input.length)) {
+       if (copy_to_user((void __user *)input.address, blob, input.length)) {
                ret = -EFAULT;
                goto e_shutdown;
        }
 
-       if (copy_to_user((void __user *)(uintptr_t)argp->data, &input,
-                        sizeof(struct sev_user_data_pek_csr)))
+       if (copy_to_user((void __user *)argp->data, &input, sizeof(input)))
                ret = -EFAULT;
 
 e_shutdown:
        if (do_shutdown)
-               sev_handle_cmd(SEV_CMD_SHUTDOWN, 0, NULL);
+               ret = sev_do_cmd(SEV_CMD_SHUTDOWN, 0, NULL);
+
 e_free_blob:
        kfree(blob);
 e_free:
@@ -408,10 +403,10 @@ static long sev_ioctl(struct file *file, unsigned int 
ioctl, unsigned long arg)
                ret = sev_ioctl_pdh_gen(&input);
                break;
 
-       case SEV_PEK_CSR: {
+       case SEV_PEK_CSR:
                ret = sev_ioctl_pek_csr(&input);
                break;
-       }
+
        default:
                ret = -EINVAL;
                goto out;

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 
(AG Nürnberg)
-- 

Reply via email to