Merge tag 'microcode_fixes_for-3.21' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp into x86/urgent

Pull microcode fixes from Borislav Petkov:

  - Two fixes hardening microcode data handling. (Quentin Casasnovas)

Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/cpu/microcode/intel.c

@@ -196,6 +196,11 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
 		struct microcode_header_intel mc_header;
 		unsigned int mc_size;
 
+		if (leftover < sizeof(mc_header)) {
+			pr_err("error! Truncated header in microcode data file\n");
+			break;
+		}
+
 		if (get_ucode_data(&mc_header, ucode_ptr, sizeof(mc_header)))
 			break;
 

arch/x86/kernel/cpu/microcode/intel_early.c

@@ -321,7 +321,11 @@ get_matching_model_microcode(int cpu, unsigned long start,
 	unsigned int mc_saved_count = mc_saved_data->mc_saved_count;
 	int i;
 
-	while (leftover) {
+	while (leftover && mc_saved_count < ARRAY_SIZE(mc_saved_tmp)) {
+
+		if (leftover < sizeof(mc_header))
+			break;
+
 		mc_header = (struct microcode_header_intel *)ucode_ptr;
 
 		mc_size = get_totalsize(mc_header);