test_firmware: Test partial read support

Add additional hooks to test_firmware to pass in support
for partial file read using request_firmware_into_buf():

	buf_size: size of buffer to request firmware into
	partial: indicates that a partial file request is being made
	file_offset: to indicate offset into file to request

Also update firmware selftests to use the new partial read test API.

Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20201002173828.2099543-17-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 142 insertions, 12 deletions

diff --git a/lib/test_firmware.c b/lib/test_firmware.c
index 06c955057756..2baa275a6ddf 100644
--- a/lib/test_firmware.c
+++ b/lib/test_firmware.c
@@ -52,6 +52,9 @@ struct test_batched_req {
  * @name: the name of the firmware file to look for
  * @into_buf: when the into_buf is used if this is true
  *	request_firmware_into_buf() will be used instead.
+ * @buf_size: size of buf to allocate when into_buf is true
+ * @file_offset: file offset to request when calling request_firmware_into_buf
+ * @partial: partial read opt when calling request_firmware_into_buf
  * @sync_direct: when the sync trigger is used if this is true
  *	request_firmware_direct() will be used instead.
  * @send_uevent: whether or not to send a uevent for async requests
@@ -91,6 +94,9 @@ struct test_batched_req {
 struct test_config {
 	char *name;
 	bool into_buf;
+	size_t buf_size;
+	size_t file_offset;
+	bool partial;
 	bool sync_direct;
 	bool send_uevent;
 	u8 num_requests;
@@ -185,6 +191,9 @@ static int __test_firmware_config_init(void)
 	test_fw_config->num_requests = TEST_FIRMWARE_NUM_REQS;
 	test_fw_config->send_uevent = true;
 	test_fw_config->into_buf = false;
+	test_fw_config->buf_size = TEST_FIRMWARE_BUF_SIZE;
+	test_fw_config->file_offset = 0;
+	test_fw_config->partial = false;
 	test_fw_config->sync_direct = false;
 	test_fw_config->req_firmware = request_firmware;
 	test_fw_config->test_result = 0;
@@ -238,28 +247,35 @@ static ssize_t config_show(struct device *dev,
 			dev_name(dev));
 
 	if (test_fw_config->name)
-		len += scnprintf(buf+len, PAGE_SIZE - len,
+		len += scnprintf(buf + len, PAGE_SIZE - len,
 				"name:\t%s\n",
 				test_fw_config->name);
 	else
-		len += scnprintf(buf+len, PAGE_SIZE - len,
+		len += scnprintf(buf + len, PAGE_SIZE - len,
 				"name:\tEMTPY\n");
 
-	len += scnprintf(buf+len, PAGE_SIZE - len,
+	len += scnprintf(buf + len, PAGE_SIZE - len,
 			"num_requests:\t%u\n", test_fw_config->num_requests);
 
-	len += scnprintf(buf+len, PAGE_SIZE - len,
+	len += scnprintf(buf + len, PAGE_SIZE - len,
 			"send_uevent:\t\t%s\n",
 			test_fw_config->send_uevent ?
 			"FW_ACTION_HOTPLUG" :
 			"FW_ACTION_NOHOTPLUG");
-	len += scnprintf(buf+len, PAGE_SIZE - len,
+	len += scnprintf(buf + len, PAGE_SIZE - len,
 			"into_buf:\t\t%s\n",
 			test_fw_config->into_buf ? "true" : "false");
-	len += scnprintf(buf+len, PAGE_SIZE - len,
+	len += scnprintf(buf + len, PAGE_SIZE - len,
+			"buf_size:\t%zu\n", test_fw_config->buf_size);
+	len += scnprintf(buf + len, PAGE_SIZE - len,
+			"file_offset:\t%zu\n", test_fw_config->file_offset);
+	len += scnprintf(buf + len, PAGE_SIZE - len,
+			"partial:\t\t%s\n",
+			test_fw_config->partial ? "true" : "false");
+	len += scnprintf(buf + len, PAGE_SIZE - len,
 			"sync_direct:\t\t%s\n",
 			test_fw_config->sync_direct ? "true" : "false");
-	len += scnprintf(buf+len, PAGE_SIZE - len,
+	len += scnprintf(buf + len, PAGE_SIZE - len,
 			"read_fw_idx:\t%u\n", test_fw_config->read_fw_idx);
 
 	mutex_unlock(&test_fw_mutex);
@@ -317,6 +333,30 @@ static ssize_t test_dev_config_show_bool(char *buf, bool val)
 	return snprintf(buf, PAGE_SIZE, "%d\n", val);
 }
 
+static int test_dev_config_update_size_t(const char *buf,
+					 size_t size,
+					 size_t *cfg)
+{
+	int ret;
+	long new;
+
+	ret = kstrtol(buf, 10, &new);
+	if (ret)
+		return ret;
+
+	mutex_lock(&test_fw_mutex);
+	*(size_t *)cfg = new;
+	mutex_unlock(&test_fw_mutex);
+
+	/* Always return full write size even if we didn't consume all */
+	return size;
+}
+
+static ssize_t test_dev_config_show_size_t(char *buf, size_t val)
+{
+	return snprintf(buf, PAGE_SIZE, "%zu\n", val);
+}
+
 static ssize_t test_dev_config_show_int(char *buf, int val)
 {
 	return snprintf(buf, PAGE_SIZE, "%d\n", val);
@@ -402,6 +442,83 @@ static ssize_t config_into_buf_show(struct device *dev,
 }
 static DEVICE_ATTR_RW(config_into_buf);
 
+static ssize_t config_buf_size_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	int rc;
+
+	mutex_lock(&test_fw_mutex);
+	if (test_fw_config->reqs) {
+		pr_err("Must call release_all_firmware prior to changing config\n");
+		rc = -EINVAL;
+		mutex_unlock(&test_fw_mutex);
+		goto out;
+	}
+	mutex_unlock(&test_fw_mutex);
+
+	rc = test_dev_config_update_size_t(buf, count,
+					   &test_fw_config->buf_size);
+
+out:
+	return rc;
+}
+
+static ssize_t config_buf_size_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	return test_dev_config_show_size_t(buf, test_fw_config->buf_size);
+}
+static DEVICE_ATTR_RW(config_buf_size);
+
+static ssize_t config_file_offset_store(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	int rc;
+
+	mutex_lock(&test_fw_mutex);
+	if (test_fw_config->reqs) {
+		pr_err("Must call release_all_firmware prior to changing config\n");
+		rc = -EINVAL;
+		mutex_unlock(&test_fw_mutex);
+		goto out;
+	}
+	mutex_unlock(&test_fw_mutex);
+
+	rc = test_dev_config_update_size_t(buf, count,
+					   &test_fw_config->file_offset);
+
+out:
+	return rc;
+}
+
+static ssize_t config_file_offset_show(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	return test_dev_config_show_size_t(buf, test_fw_config->file_offset);
+}
+static DEVICE_ATTR_RW(config_file_offset);
+
+static ssize_t config_partial_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	return test_dev_config_update_bool(buf,
+					   count,
+					   &test_fw_config->partial);
+}
+
+static ssize_t config_partial_show(struct device *dev,
+				   struct device_attribute *attr,
+				   char *buf)
+{
+	return test_dev_config_show_bool(buf, test_fw_config->partial);
+}
+static DEVICE_ATTR_RW(config_partial);
+
 static ssize_t config_sync_direct_store(struct device *dev,
 					struct device_attribute *attr,
 					const char *buf, size_t count)
@@ -659,11 +776,21 @@ static int test_fw_run_batch_request(void *data)
 		if (!test_buf)
 			return -ENOSPC;
 
-		req->rc = request_firmware_into_buf(&req->fw,
-						    req->name,
-						    req->dev,
-						    test_buf,
-						    TEST_FIRMWARE_BUF_SIZE);
+		if (test_fw_config->partial)
+			req->rc = request_partial_firmware_into_buf
+						(&req->fw,
+						 req->name,
+						 req->dev,
+						 test_buf,
+						 test_fw_config->buf_size,
+						 test_fw_config->file_offset);
+		else
+			req->rc = request_firmware_into_buf
+						(&req->fw,
+						 req->name,
+						 req->dev,
+						 test_buf,
+						 test_fw_config->buf_size);
 		if (!req->fw)
 			kfree(test_buf);
 	} else {
@@ -936,6 +1063,9 @@ static struct attribute *test_dev_attrs[] = {
 	TEST_FW_DEV_ATTR(config_name),
 	TEST_FW_DEV_ATTR(config_num_requests),
 	TEST_FW_DEV_ATTR(config_into_buf),
+	TEST_FW_DEV_ATTR(config_buf_size),
+	TEST_FW_DEV_ATTR(config_file_offset),
+	TEST_FW_DEV_ATTR(config_partial),
 	TEST_FW_DEV_ATTR(config_sync_direct),
 	TEST_FW_DEV_ATTR(config_send_uevent),
 	TEST_FW_DEV_ATTR(config_read_fw_idx),