linux-kernel - [PATCH v2 1/3] dell_rbu: Don't fallback to userhelper

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Message-Id: <1463423270-24348-1-git-send-email-mario_limonciello@dell.com>
Date:	Mon, 16 May 2016 13:27:48 -0500
From:	Mario Limonciello <mario_limonciello@...l.com>
To:	ming.lei@...onical.com
Cc:	LKML <linux-kernel@...r.kernel.org>,
	Mario Limonciello <mario_limonciello@...l.com>
Subject: [PATCH v2 1/3] dell_rbu: Don't fallback to userhelper

when loading firmware dell_rbu previously would allow a userspace
application to craft the payload after dell_rbu was loaded and
abuse the udev userspace API.

Instead require the payload to be crafted and placed in
/lib/firmware/dell_rbu ahead of time.

This adjusts dell_rbu to immediately load the firmware from
/lib/firmware/dell_rbu when "init" is passed into image_type using the
kernel helper.

Signed-off-by: Mario Limonciello <mario_limonciello@...l.com>
---
 drivers/firmware/Kconfig    | 1 -
 drivers/firmware/dell_rbu.c | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index 6664f11..85afe59 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -86,7 +86,6 @@ config DELL_RBU
 	tristate "BIOS update support for DELL systems via sysfs"
 	depends on X86
 	select FW_LOADER
-	select FW_LOADER_USER_HELPER
 	help
 	 Say m if you want to have the option of updating the BIOS for your
 	 DELL system. Note you need a Dell OpenManage or Dell Update package (DUP)
diff --git a/drivers/firmware/dell_rbu.c b/drivers/firmware/dell_rbu.c
index 2f452f1..77b2a77 100644
--- a/drivers/firmware/dell_rbu.c
+++ b/drivers/firmware/dell_rbu.c
@@ -620,7 +620,7 @@ static ssize_t write_rbu_image_type(struct file *filp, struct kobject *kobj,
 		if (!rbu_data.entry_created) {
 			spin_unlock(&rbu_data.lock);
 			req_firm_rc = request_firmware_nowait(THIS_MODULE,
-				FW_ACTION_NOHOTPLUG, "dell_rbu",
+				FW_ACTION_HOTPLUG, "dell_rbu",
 				&rbu_device->dev, GFP_KERNEL, &context,
 				callbackfn_rbu);
 			if (req_firm_rc) {
-- 
2.7.4