[PATCH AUTOSEL 4.14 120/371] platform/x86: wmi: fix potential null pointer dereference

[PATCH AUTOSEL 4.14 120/371] platform/x86: wmi: fix potential null pointer dereference

[Sasha Levin]

From: Mattias Jacobsson <2pi@mok.nu>

[ Upstream commit c355ec651a8941864549f2586f969d0eb7bf499a ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 7f8fa42a1084..a56e997816b2 100644
--- a/drivers/platform/x86/wmi.c
+++ b/drivers/platform/x86/wmi.c
@@ -748,6 +748,9 @@ 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;
 
-- 
2.20.1

[PATCH AUTOSEL 4.14 163/371] platform/x86: alienware-wmi: fix kfree on potentially uninitialized pointer

[Sasha Levin]

From: Colin Ian King <colin.king@canonical.com>

[ Upstream commit 98e2630284ab741804bd0713e932e725466f2f84 ]

Currently the kfree of output.pointer can be potentially freeing
an uninitalized pointer in the case where out_data is NULL. Fix this
by reworking the case where out_data is not-null to perform the
ACPI status check and also the kfree of outpoint.pointer in one block
and hence ensuring the pointer is only freed when it has been used.

Also replace the if (ptr != NULL) idiom with just if (ptr).

Fixes: ff0e9f26288d ("platform/x86: alienware-wmi: Correct a memory leak")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/platform/x86/alienware-wmi.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/platform/x86/alienware-wmi.c b/drivers/platform/x86/alienware-wmi.c
index e335b18da20f..cbd84e2e3bd4 100644
--- a/drivers/platform/x86/alienware-wmi.c
+++ b/drivers/platform/x86/alienware-wmi.c
@@ -505,23 +505,22 @@ static acpi_status alienware_wmax_command(struct wmax_basic_args *in_args,
 
 	input.length = (acpi_size) sizeof(*in_args);
 	input.pointer = in_args;
-	if (out_data != NULL) {
+	if (out_data) {
 		output.length = ACPI_ALLOCATE_BUFFER;
 		output.pointer = NULL;
 		status = wmi_evaluate_method(WMAX_CONTROL_GUID, 0,
 					     command, &input, &output);
-	} else
+		if (ACPI_SUCCESS(status)) {
+			obj = (union acpi_object *)output.pointer;
+			if (obj && obj->type == ACPI_TYPE_INTEGER)
+				*out_data = (u32)obj->integer.value;
+		}
+		kfree(output.pointer);
+	} else {
 		status = wmi_evaluate_method(WMAX_CONTROL_GUID, 0,
 					     command, &input, NULL);
-
-	if (ACPI_SUCCESS(status) && out_data != NULL) {
-		obj = (union acpi_object *)output.pointer;
-		if (obj && obj->type == ACPI_TYPE_INTEGER)
-			*out_data = (u32) obj->integer.value;
 	}
-	kfree(output.pointer);
 	return status;
-
 }
 
 /*
-- 
2.20.1

[PATCH AUTOSEL 4.14 195/371] platform/x86: alienware-wmi: printing the wrong error code

[Sasha Levin]

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit 6d1f8b3d75419a8659ac916a1e9543bb3513a882 ]

The "out_data" variable is uninitialized at the point.  Originally, this
used to print "status" instead and that seems like the correct thing to
print.

Fixes: bc2ef884320b ("alienware-wmi: For WMAX HDMI method, introduce a way to query HDMI cable status")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/platform/x86/alienware-wmi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/platform/x86/alienware-wmi.c b/drivers/platform/x86/alienware-wmi.c
index cbd84e2e3bd4..2c82188f8486 100644
--- a/drivers/platform/x86/alienware-wmi.c
+++ b/drivers/platform/x86/alienware-wmi.c
@@ -570,7 +570,7 @@ static ssize_t show_hdmi_source(struct device *dev,
 			return scnprintf(buf, PAGE_SIZE,
 					 "input [gpu] unknown\n");
 	}
-	pr_err("alienware-wmi: unknown HDMI source status: %d\n", out_data);
+	pr_err("alienware-wmi: unknown HDMI source status: %u\n", status);
 	return scnprintf(buf, PAGE_SIZE, "input gpu [unknown]\n");
 }
 
-- 
2.20.1