Re: [Qemu-devel] [PATCH v5.2 for 2.13 1/4] tpm: extend TPM emulator with state migration support

[Stefan Berger <stefanb@linux.vnet.ibm.com>]

On 03/21/2018 01:14 PM, Dr. David Alan Gilbert wrote:
> * Stefan Berger (stefanb@linux.vnet.ibm.com) wrote:
>> +
>> +    if (totlength > 0) {
>> +        tsb->buffer = g_try_malloc(totlength);
>> +        if (!tsb->buffer) {
>> +            error_report("tpm-emulator: Out of memory allocating %u bytes",
>> +                         totlength);
>> +            return -1;
>> +        }
>> +
>> +        n = qemu_chr_fe_read_all(&tpm_emu->ctrl_chr, tsb->buffer, totlength);
>> +        if (n != totlength) {
>> +            error_report("tpm-emulator: Could not read stateblob (type %d); "
>> +                         "expected %u bytes, got %zd",
>> +                         type, totlength, n);
> I think you need to free tsb->buffer here.

tpm_emulator_get_state_blobs() below clears all 3 buffers in case one 
error is encountered.

>
> Other than that, I think:
>
> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
>
>
>> +            return -1;
>> +        }
>> +    }
>> +    tsb->size = totlength;
>> +
>> +    trace_tpm_emulator_get_state_blob(type, tsb->size, *flags);
>> +
>> +    return 0;
>> +}
>> +
>> +static int tpm_emulator_get_state_blobs(TPMEmulator *tpm_emu)
>> +{
>> +    TPMBlobBuffers *state_blobs = &tpm_emu->state_blobs;
>> +
>> +    if (tpm_emulator_get_state_blob(tpm_emu, PTM_BLOB_TYPE_PERMANENT,
>> +                                    &state_blobs->permanent,
>> +                                    &state_blobs->permanent_flags) < 0 ||
>> +        tpm_emulator_get_state_blob(tpm_emu, PTM_BLOB_TYPE_VOLATILE,
>> +                                    &state_blobs->volatil,
>> +                                    &state_blobs->volatil_flags) < 0 ||
>> +        tpm_emulator_get_state_blob(tpm_emu, PTM_BLOB_TYPE_SAVESTATE,
>> +                                    &state_blobs->savestate,
>> +                                    &state_blobs->savestate_flags) < 0) {
>> +        goto err_exit;
>> +    }
>> +
>> +    return 0;
>> +
>> + err_exit:
>> +    tpm_sized_buffer_reset(&state_blobs->volatil);
>> +    tpm_sized_buffer_reset(&state_blobs->permanent);
>> +    tpm_sized_buffer_reset(&state_blobs->savestate);

^^^ here

>> +
>> +    return -1;
>> +}