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[next] HID: playstation: fix array size comparison (off-by-one)

Message ID 20210215163921.84283-1-colin.king@canonical.com
State Accepted
Commit 50ab1ffd7c41c5c7759b62fb42d3006b751bb12b
Headers show
Series [next] HID: playstation: fix array size comparison (off-by-one) | expand

Commit Message

Colin King Feb. 15, 2021, 4:39 p.m. UTC
From: Colin Ian King <colin.king@canonical.com>

The comparison of value with the array size ps_gamepad_hat_mapping
appears to be off-by-one. Fix this by using >= rather than > for the
size comparison.

Addresses-Coverity: ("Out-of-bounds read")
Fixes: bc2e15a9a022 ("HID: playstation: initial DualSense USB support.")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/hid/hid-playstation.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Benjamin Tissoires Feb. 17, 2021, 8:04 p.m. UTC | #1
On Mon, Feb 15, 2021 at 5:39 PM Colin King <colin.king@canonical.com> wrote:
>

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

>

> The comparison of value with the array size ps_gamepad_hat_mapping

> appears to be off-by-one. Fix this by using >= rather than > for the

> size comparison.

>

> Addresses-Coverity: ("Out-of-bounds read")

> Fixes: bc2e15a9a022 ("HID: playstation: initial DualSense USB support.")

> Signed-off-by: Colin Ian King <colin.king@canonical.com>

> ---


Good catch.

Applied to for-5.12/playstation-v2

Cheers,
Benjamin

>  drivers/hid/hid-playstation.c | 2 +-

>  1 file changed, 1 insertion(+), 1 deletion(-)

>

> diff --git a/drivers/hid/hid-playstation.c b/drivers/hid/hid-playstation.c

> index 408b651174cf..568a3a067c88 100644

> --- a/drivers/hid/hid-playstation.c

> +++ b/drivers/hid/hid-playstation.c

> @@ -1064,7 +1064,7 @@ static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *r

>         input_report_abs(ds->gamepad, ABS_RZ, ds_report->rz);

>

>         value = ds_report->buttons[0] & DS_BUTTONS0_HAT_SWITCH;

> -       if (value > ARRAY_SIZE(ps_gamepad_hat_mapping))

> +       if (value >= ARRAY_SIZE(ps_gamepad_hat_mapping))

>                 value = 8; /* center */

>         input_report_abs(ds->gamepad, ABS_HAT0X, ps_gamepad_hat_mapping[value].x);

>         input_report_abs(ds->gamepad, ABS_HAT0Y, ps_gamepad_hat_mapping[value].y);

> --

> 2.30.0

>
diff mbox series

Patch

diff --git a/drivers/hid/hid-playstation.c b/drivers/hid/hid-playstation.c
index 408b651174cf..568a3a067c88 100644
--- a/drivers/hid/hid-playstation.c
+++ b/drivers/hid/hid-playstation.c
@@ -1064,7 +1064,7 @@  static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *r
 	input_report_abs(ds->gamepad, ABS_RZ, ds_report->rz);
 
 	value = ds_report->buttons[0] & DS_BUTTONS0_HAT_SWITCH;
-	if (value > ARRAY_SIZE(ps_gamepad_hat_mapping))
+	if (value >= ARRAY_SIZE(ps_gamepad_hat_mapping))
 		value = 8; /* center */
 	input_report_abs(ds->gamepad, ABS_HAT0X, ps_gamepad_hat_mapping[value].x);
 	input_report_abs(ds->gamepad, ABS_HAT0Y, ps_gamepad_hat_mapping[value].y);