[PATCH 3.2 070/149] HID: LG: validate HID output report details

From: Ben Hutchings
Date: Mon Oct 21 2013 - 05:17:28 EST


3.2.52-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Kees Cook <keescook@xxxxxxxxxxxx>

commit 0fb6bd06e06792469acc15bbe427361b56ada528 upstream.

A HID device could send a malicious output report that would cause the
lg, lg3, and lg4 HID drivers to write beyond the output report allocation
during an event, causing a heap overflow:

[ 325.245240] usb 1-1: New USB device found, idVendor=046d, idProduct=c287
...
[ 414.518960] BUG kmalloc-4096 (Not tainted): Redzone overwritten

Additionally, while lg2 did correctly validate the report details, it was
cleaned up and shortened.

CVE-2013-2893

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/hid/hid-lg2ff.c | 19 +++----------------
drivers/hid/hid-lg3ff.c | 29 ++++++-----------------------
drivers/hid/hid-lg4ff.c | 20 +-------------------
drivers/hid/hid-lgff.c | 17 ++---------------
4 files changed, 12 insertions(+), 73 deletions(-)

--- a/drivers/hid/hid-lg2ff.c
+++ b/drivers/hid/hid-lg2ff.c
@@ -66,26 +66,13 @@ int lg2ff_init(struct hid_device *hid)
struct hid_report *report;
struct hid_input *hidinput = list_entry(hid->inputs.next,
struct hid_input, list);
- struct list_head *report_list =
- &hid->report_enum[HID_OUTPUT_REPORT].report_list;
struct input_dev *dev = hidinput->input;
int error;

- if (list_empty(report_list)) {
- hid_err(hid, "no output report found\n");
+ /* Check that the report looks ok */
+ report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7);
+ if (!report)
return -ENODEV;
- }
-
- report = list_entry(report_list->next, struct hid_report, list);
-
- if (report->maxfield < 1) {
- hid_err(hid, "output report is empty\n");
- return -ENODEV;
- }
- if (report->field[0]->report_count < 7) {
- hid_err(hid, "not enough values in the field\n");
- return -ENODEV;
- }

lg2ff = kmalloc(sizeof(struct lg2ff_device), GFP_KERNEL);
if (!lg2ff)
--- a/drivers/hid/hid-lg3ff.c
+++ b/drivers/hid/hid-lg3ff.c
@@ -68,10 +68,11 @@ static int hid_lg3ff_play(struct input_d
int x, y;

/*
- * Maxusage should always be 63 (maximum fields)
- * likely a better way to ensure this data is clean
+ * Available values in the field should always be 63, but we only use up to
+ * 35. Instead, clear the entire area, however big it is.
*/
- memset(report->field[0]->value, 0, sizeof(__s32)*report->field[0]->maxusage);
+ memset(report->field[0]->value, 0,
+ sizeof(__s32) * report->field[0]->report_count);

switch (effect->type) {
case FF_CONSTANT:
@@ -131,32 +132,14 @@ static const signed short ff3_joystick_a
int lg3ff_init(struct hid_device *hid)
{
struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
- struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
struct input_dev *dev = hidinput->input;
- struct hid_report *report;
- struct hid_field *field;
const signed short *ff_bits = ff3_joystick_ac;
int error;
int i;

- /* Find the report to use */
- if (list_empty(report_list)) {
- hid_err(hid, "No output report found\n");
- return -1;
- }
-
/* Check that the report looks ok */
- report = list_entry(report_list->next, struct hid_report, list);
- if (!report) {
- hid_err(hid, "NULL output report\n");
- return -1;
- }
-
- field = report->field[0];
- if (!field) {
- hid_err(hid, "NULL field\n");
- return -1;
- }
+ if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 35))
+ return -ENODEV;

/* Assume single fixed device G940 */
for (i = 0; ff_bits[i] >= 0; i++)
--- a/drivers/hid/hid-lg4ff.c
+++ b/drivers/hid/hid-lg4ff.c
@@ -339,33 +339,15 @@ static ssize_t lg4ff_range_store(struct
int lg4ff_init(struct hid_device *hid)
{
struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
- struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
struct input_dev *dev = hidinput->input;
- struct hid_report *report;
- struct hid_field *field;
struct lg4ff_device_entry *entry;
struct usb_device_descriptor *udesc;
int error, i, j;
__u16 bcdDevice, rev_maj, rev_min;

- /* Find the report to use */
- if (list_empty(report_list)) {
- hid_err(hid, "No output report found\n");
- return -1;
- }
-
/* Check that the report looks ok */
- report = list_entry(report_list->next, struct hid_report, list);
- if (!report) {
- hid_err(hid, "NULL output report\n");
- return -1;
- }
-
- field = report->field[0];
- if (!field) {
- hid_err(hid, "NULL field\n");
+ if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7))
return -1;
- }

/* Check what wheel has been connected */
for (i = 0; i < ARRAY_SIZE(lg4ff_devices); i++) {
--- a/drivers/hid/hid-lgff.c
+++ b/drivers/hid/hid-lgff.c
@@ -130,27 +130,14 @@ static void hid_lgff_set_autocenter(stru
int lgff_init(struct hid_device* hid)
{
struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
- struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
struct input_dev *dev = hidinput->input;
- struct hid_report *report;
- struct hid_field *field;
const signed short *ff_bits = ff_joystick;
int error;
int i;

- /* Find the report to use */
- if (list_empty(report_list)) {
- hid_err(hid, "No output report found\n");
- return -1;
- }
-
/* Check that the report looks ok */
- report = list_entry(report_list->next, struct hid_report, list);
- field = report->field[0];
- if (!field) {
- hid_err(hid, "NULL field\n");
- return -1;
- }
+ if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7))
+ return -ENODEV;

for (i = 0; i < ARRAY_SIZE(devices); i++) {
if (dev->id.vendor == devices[i].idVendor &&

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