x86, microcode, AMD: Release firmware on error

When the ucode magic is wrong, for whatever reason, we don't release the
loaded firmware binary and its related resources. Make sure we do. Also,
fix function naming to fit this driver's convention and shorten variable
names.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Acked-by: Andreas Herrmann <Andreas.Herrmann3@amd.com>

arch/x86/kernel/microcode_amd.c

@@ -278,27 +278,29 @@ generic_load_microcode(int cpu, const u8 *data, size_t size)
 	return state;
 }
 
-static enum ucode_state request_microcode_fw(int cpu, struct device *device)
+static enum ucode_state request_microcode_amd(int cpu, struct device *device)
 {
 	const char *fw_name = "amd-ucode/microcode_amd.bin";
-	const struct firmware *firmware;
-	enum ucode_state ret;
+	const struct firmware *fw;
+	enum ucode_state ret = UCODE_NFOUND;
 
-	if (request_firmware(&firmware, fw_name, device)) {
+	if (request_firmware(&fw, fw_name, device)) {
 		printk(KERN_ERR "microcode: failed to load file %s\n", fw_name);
-		return UCODE_NFOUND;
+		goto out;
 	}
 
-	if (*(u32 *)firmware->data != UCODE_MAGIC) {
-		pr_err("invalid UCODE_MAGIC (0x%08x)\n",
-		       *(u32 *)firmware->data);
-		return UCODE_ERROR;
+	ret = UCODE_ERROR;
+	if (*(u32 *)fw->data != UCODE_MAGIC) {
+		pr_err("Invalid UCODE_MAGIC (0x%08x)\n", *(u32 *)fw->data);
+		goto fw_release;
 	}
 
-	ret = generic_load_microcode(cpu, firmware->data, firmware->size);
+	ret = generic_load_microcode(cpu, fw->data, fw->size);
 
-	release_firmware(firmware);
+fw_release:
+	release_firmware(fw);
 
+out:
 	return ret;
 }
 
@@ -319,7 +321,7 @@ static void microcode_fini_cpu_amd(int cpu)
 
 static struct microcode_ops microcode_amd_ops = {
 	.request_microcode_user           = request_microcode_user,
-	.request_microcode_fw             = request_microcode_fw,
+	.request_microcode_fw             = request_microcode_amd,
 	.collect_cpu_info                 = collect_cpu_info_amd,
 	.apply_microcode                  = apply_microcode_amd,
 	.microcode_fini_cpu               = microcode_fini_cpu_amd,