@@ -211,9 +211,16 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
efispecid = (struct tcg_efi_specid_event_head *)event_header->event;
- /* Check if event is malformed. */
+ /*
+ * Perform validation of the event in order to identify malformed
+ * events. This function may be asked to parse arbitrary byte sequences
+ * immediately following a valid event log. The caller expects this
+ * function to recognize that the byte sequence is not a valid event
+ * and to return an event size of 0.
+ */
if (memcmp(efispecid->signature, TCG_SPECID_SIG,
- sizeof(TCG_SPECID_SIG)) || count > efispecid->num_algs) {
+ sizeof(TCG_SPECID_SIG)) ||
+ !efispecid->num_algs || count != efispecid->num_algs) {
size = 0;
goto out;
}