From c355ec651a8941864549f2586f969d0eb7bf499a Mon Sep 17 00:00:00 2001
From: Mattias Jacobsson <2pi@mok.nu>
Date: Wed, 30 Jan 2019 16:14:24 +0100
Subject: [PATCH] platform/x86: wmi: fix potential null pointer dereference
Git-commit: c355ec651a8941864549f2586f969d0eb7bf499a
Patch-mainline: v5.1-rc1
References: bsc#1111666
In the function wmi_dev_match() the variable id is dereferenced without
first performing a NULL check. The variable can for example be NULL if
a WMI driver is registered without specifying the id_table field in
struct wmi_driver.
Add a NULL check and return that the driver can't handle the device if
the variable is NULL.
Fixes: 844af950da94 ("platform/x86: wmi: Turn WMI into a bus driver")
Signed-off-by: Mattias Jacobsson <2pi@mok.nu>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/platform/x86/wmi.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
index bea35be68706..b0f3d8ecd898 100644
--- a/drivers/platform/x86/wmi.c
+++ b/drivers/platform/x86/wmi.c
@@ -768,6 +768,9 @@ static int wmi_dev_match(struct device *dev, struct device_driver *driver)
struct wmi_block *wblock = dev_to_wblock(dev);
const struct wmi_device_id *id = wmi_driver->id_table;
+ if (id == NULL)
+ return 0;
+
while (id->guid_string) {
uuid_le driver_guid;
--
2.16.4