HID: core: Fix size as type u32

BugLink: http://bugs.launchpad.net/bugs/1768429

commit 6de0b13c upstream.

When size is negative, calling memset will make segment fault.
Declare the size as type u32 to keep memset safe.

size in struct hid_report is unsigned, fix return type of
hid_report_len to u32.

Cc: stable@vger.kernel.org
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/hid/hid-core.c

@@ -1331,7 +1331,7 @@ u8 *hid_alloc_report_buf(struct hid_report *report, gfp_t flags)
 	 * of implement() working on 8 byte chunks
 	 */
 
-	int len = hid_report_len(report) + 7;
+	u32 len = hid_report_len(report) + 7;
 
 	return kmalloc(len, flags);
 }
@@ -1396,7 +1396,7 @@ void __hid_request(struct hid_device *hid, struct hid_report *report,
 {
 	char *buf;
 	int ret;
-	int len;
+	u32 len;
 
 	buf = hid_alloc_report_buf(report, GFP_KERNEL);
 	if (!buf)
@@ -1422,14 +1422,14 @@ void __hid_request(struct hid_device *hid, struct hid_report *report,
 }
 EXPORT_SYMBOL_GPL(__hid_request);
 
-int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size,
+int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, u32 size,
 		int interrupt)
 {
 	struct hid_report_enum *report_enum = hid->report_enum + type;
 	struct hid_report *report;
 	struct hid_driver *hdrv;
 	unsigned int a;
-	int rsize, csize = size;
+	u32 rsize, csize = size;
 	u8 *cdata = data;
 	int ret = 0;
 
@@ -1487,7 +1487,7 @@ EXPORT_SYMBOL_GPL(hid_report_raw_event);
  *
  * This is data entry for lower layers.
  */
-int hid_input_report(struct hid_device *hid, int type, u8 *data, int size, int interrupt)
+int hid_input_report(struct hid_device *hid, int type, u8 *data, u32 size, int interrupt)
 {
 	struct hid_report_enum *report_enum;
 	struct hid_driver *hdrv;

include/linux/hid.h

@@ -793,7 +793,7 @@ extern int hidinput_connect(struct hid_device *hid, unsigned int force);
 extern void hidinput_disconnect(struct hid_device *);
 
 int hid_set_field(struct hid_field *, unsigned, __s32);
-int hid_input_report(struct hid_device *, int type, u8 *, int, int);
+int hid_input_report(struct hid_device *, int type, u8 *, u32, int);
 int hidinput_find_field(struct hid_device *hid, unsigned int type, unsigned int code, struct hid_field **field);
 struct hid_field *hidinput_get_led_field(struct hid_device *hid);
 unsigned int hidinput_count_leds(struct hid_device *hid);
@@ -1098,13 +1098,13 @@ static inline void hid_hw_wait(struct hid_device *hdev)
  *
  * @report: the report we want to know the length
  */
-static inline int hid_report_len(struct hid_report *report)
+static inline u32 hid_report_len(struct hid_report *report)
 {
 	/* equivalent to DIV_ROUND_UP(report->size, 8) + !!(report->id > 0) */
 	return ((report->size - 1) >> 3) + 1 + (report->id > 0);
 }
 
-int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size,
+int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, u32 size,
 		int interrupt);
 
 /* HID quirks API */