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

[Stefan Berger]

On 03/21/2018 01:14 PM, Dr. David Alan Gilbert wrote:
> * Stefan Berger (address@hidden) 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 <address@hidden>
>
>
> > +            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;
> > +}