[PATCH 1/2] firmware_loader: builtin: ignore 0-size firmware

[Dmitry Torokhov]

Currently, the builtin firmware loader allows 0-size firmware to be
returned successfully to drivers. This differs from all other loading
mechanisms (filesystem, sysfs fallback) which reject 0-byte files, and
forces drivers to add boilerplate size checks.

Modify firmware_request_builtin() to reject 0-size firmware. This will
also result in firmware loader falling back to other mechanisms if an
empty built-in firmware is present.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---
 drivers/base/firmware_loader/builtin/main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/base/firmware_loader/builtin/main.c b/drivers/base/firmware_loader/builtin/main.c
index d36befebb1b9..1dcebe8e7f8e 100644
--- a/drivers/base/firmware_loader/builtin/main.c
+++ b/drivers/base/firmware_loader/builtin/main.c
@@ -53,6 +53,8 @@ bool firmware_request_builtin(struct firmware *fw, const char *name)
 
 	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
 		if (strcmp(name, b_fw->name) == 0) {
+			if (b_fw->size == 0)
+				return false;
 			fw->size = b_fw->size;
 			fw->data = b_fw->data;
 			return true;
-- 
2.54.0.545.g6539524ca2-goog