[PATCH 17/20] staging: gasket: top ioctl handler add __user annotations

From: Todd Poynor
Date: Sat Jul 21 2018 - 08:58:04 EST


From: Todd Poynor <toddpoynor@xxxxxxxxxx>

Add __user annotation to gasket_core top-level ioctl handling pointer
arguments, for sparse checking.

Reported-by: Dmitry Torokhov <dtor@xxxxxxxxxxxx>
Signed-off-by: Zhongze Hu <frankhu@xxxxxxxxxxxx>
Signed-off-by: Todd Poynor <toddpoynor@xxxxxxxxxx>
---
drivers/staging/gasket/gasket_core.c | 6 ++++--
drivers/staging/gasket/gasket_core.h | 7 +++++--
2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/gasket/gasket_core.c b/drivers/staging/gasket/gasket_core.c
index 254fb392c05c1..40e46ca5228c8 100644
--- a/drivers/staging/gasket/gasket_core.c
+++ b/drivers/staging/gasket/gasket_core.c
@@ -14,6 +14,7 @@
#include "gasket_page_table.h"
#include "gasket_sysfs.h"

+#include <linux/compiler.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/init.h>
@@ -1781,6 +1782,7 @@ static long gasket_ioctl(struct file *filp, uint cmd, ulong arg)
{
struct gasket_dev *gasket_dev;
const struct gasket_driver_desc *driver_desc;
+ void __user *argp = (void __user *)arg;
char path[256];

if (!filp)
@@ -1810,14 +1812,14 @@ static long gasket_ioctl(struct file *filp, uint cmd, ulong arg)
* check_and_invoke_callback.
*/
if (driver_desc->ioctl_handler_cb)
- return driver_desc->ioctl_handler_cb(filp, cmd, arg);
+ return driver_desc->ioctl_handler_cb(filp, cmd, argp);

gasket_log_error(
gasket_dev, "Received unknown ioctl 0x%x", cmd);
return -EINVAL;
}

- return gasket_handle_ioctl(filp, cmd, arg);
+ return gasket_handle_ioctl(filp, cmd, argp);
}

int gasket_reset(struct gasket_dev *gasket_dev, uint reset_type)
diff --git a/drivers/staging/gasket/gasket_core.h b/drivers/staging/gasket/gasket_core.h
index 7ea1df123ba5d..bf4ed3769efb2 100644
--- a/drivers/staging/gasket/gasket_core.h
+++ b/drivers/staging/gasket/gasket_core.h
@@ -314,9 +314,12 @@ struct gasket_dev {
struct hlist_node legacy_hlist_node;
};

+/* Type of the ioctl handler callback. */
+typedef long (*gasket_ioctl_handler_cb_t)
+ (struct file *file, uint cmd, void __user *argp);
/* Type of the ioctl permissions check callback. See below. */
typedef int (*gasket_ioctl_permissions_cb_t)(
- struct file *filp, uint cmd, ulong arg);
+ struct file *filp, uint cmd, void __user *argp);

/*
* Device type descriptor.
@@ -550,7 +553,7 @@ struct gasket_driver_desc {
* return -EINVAL. Should return an error status (either -EINVAL or
* the error result of the ioctl being handled).
*/
- long (*ioctl_handler_cb)(struct file *filp, uint cmd, ulong arg);
+ gasket_ioctl_handler_cb_t ioctl_handler_cb;

/*
* device_status_cb: Callback to determine device health.
--
2.18.0.233.g985f88cf7e-goog