diff --git a/hw/smbios/smbios.c b/hw/smbios/smbios.c
index d993448087..8b30906e50 100644
--- a/hw/smbios/smbios.c
+++ b/hw/smbios/smbios.c
@@ -365,6 +365,13 @@ static void smbios_register_config(void)
 
 opts_init(smbios_register_config);
 
+/*
+ * The SMBIOS 2.1 "structure table length" field in the
+ * entry point uses a 16-bit integer, so we're limited
+ * in total table size
+ */
+#define SMBIOS_21_MAX_TABLES_LEN 0xffff
+
 static void smbios_validate_table(MachineState *ms)
 {
     uint32_t expect_t4_count = smbios_legacy ?
@@ -375,6 +382,13 @@ static void smbios_validate_table(MachineState *ms)
                      expect_t4_count, smbios_type4_count);
         exit(1);
     }
+
+    if (smbios_ep_type == SMBIOS_ENTRY_POINT_21 &&
+        smbios_tables_len > SMBIOS_21_MAX_TABLES_LEN) {
+        error_report("SMBIOS 2.1 table length %zu exceeds %d",
+                     smbios_tables_len, SMBIOS_21_MAX_TABLES_LEN);
+        exit(1);
+    }
 }