On 3/19/26 9:53 AM, Arun Menon wrote:
- Double the size from 4096 to 8192 so that we can have bigger buffer
enabling support for PQC algorithms in the TPM TIS interface.
- v185 of TCG TPM rolls out PQC algorithm support. [1]
[1] section 46
https://members.trustedcomputinggroup.org/wg/TCG/document/previewpdf/45151
Signed-off-by: Arun Menon <[email protected]>
---
hw/tpm/tpm_tis.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/hw/tpm/tpm_tis.h b/hw/tpm/tpm_tis.h
index 184632ff66..0df35d5a54 100644
--- a/hw/tpm/tpm_tis.h
+++ b/hw/tpm/tpm_tis.h
@@ -33,7 +33,7 @@
#define TPM_TIS_IS_VALID_LOCTY(x) ((x) < TPM_TIS_NUM_LOCALITIES)
-#define TPM_TIS_BUFFER_MAX 4096
+#define TPM_TIS_BUFFER_MAX 8192
Unfortunately TIS uses a fixed-size buffer that would now become bigger:
typedef struct TPMState {
MemoryRegion mmio;
unsigned char buffer[TPM_TIS_BUFFER_MAX]; <-- now 8192; before 4096
static const VMStateDescription vmstate_tpm_tis_isa = {
.name = "tpm-tis",
.version_id = 0,
.pre_save = tpm_tis_pre_save_isa,
.fields = (const VMStateField[]) {
VMSTATE_BUFFER(state.buffer, TPMStateISA), <-- now 8192;
before 4096
VMSTATE_UINT16(state.rw_offset, TPMStateISA),
Problem would be if an older version of the TIS (with size 4096) then
receives this 8192 buffer, we would (probably) get a buffer overflow.
typedef enum {
TPM_TIS_STATE_IDLE = 0,
