On Thu, Oct 19, 2017 at 09:33:53PM -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 <[email protected]> > Cc: "Radim Krčmář" <[email protected]> > Cc: Borislav Petkov <[email protected]> > Cc: Herbert Xu <[email protected]> > Cc: Gary Hook <[email protected]> > Cc: Tom Lendacky <[email protected]> > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > Signed-off-by: Brijesh Singh <[email protected]> > --- > drivers/crypto/ccp/psp-dev.c | 69 > ++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 69 insertions(+)
Improvements-by: Borislav Petkov <[email protected]> > +static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp) > +{ > + struct sev_user_data_pek_csr input; > + struct sev_data_pek_csr *data; > + void *blob = NULL; > + int ret, err; > + > + if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) > + return -EFAULT; > + > + data = kzalloc(sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + /* userspace wants to query CSR length */ > + if (!input.address || !input.length) > + goto cmd; > + > + /* 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) { > + 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; > + > +cmd: > + ret = sev_platform_init(NULL, &argp->error); > + if (ret) > + goto e_free_blob; > + > + ret = sev_do_cmd(SEV_CMD_PEK_CSR, data, &argp->error); This is the same issue: nothing is handling the case where sev_do_cmd() here fails. If it doesn't matter, then you should simply do: sev_do_cmd(SEV_CMD_PEK_CSR, data, &argp->error); along with explaining why we don't care about the command failing. But simply writing into ret to overwrite it later, looks strange. -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. --
