2021-05-19 19:06:08

by Qiang Ma

Subject: [PATCH] Input: psmouse - fix psmouse detect function is a NULL pointer

Add a check for psmouse_do_detect(), when the detect is NULL pointer,
returning false, avoiding this possible NULL pointer exception.

Signed-off-by: Qiang Ma <[email protected]>
---
drivers/input/mouse/psmouse-base.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
index 0b4a3039f312..86b095728587 100644
--- a/drivers/input/mouse/psmouse-base.c
+++ b/drivers/input/mouse/psmouse-base.c
@@ -1006,6 +1006,9 @@ static bool psmouse_do_detect(int (*detect)(struct psmouse *, bool),
if (set_properties)
psmouse_apply_defaults(psmouse);

+ if (!detect)
+ return false;
+
return detect(psmouse, set_properties) == 0;
}

--
2.20.1

2021-06-02 08:06:49

by Dmitry Torokhov

Subject: Re: [PATCH] Input: psmouse - fix psmouse detect function is a NULL pointer

Hi Qiang,

On Wed, May 19, 2021 at 11:23:35AM +0800, Qiang Ma wrote:
> Add a check for psmouse_do_detect(), when the detect is NULL pointer,
> returning false, avoiding this possible NULL pointer exception.
>
> Signed-off-by: Qiang Ma <[email protected]>
> ---
> drivers/input/mouse/psmouse-base.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
> index 0b4a3039f312..86b095728587 100644
> --- a/drivers/input/mouse/psmouse-base.c
> +++ b/drivers/input/mouse/psmouse-base.c
> @@ -1006,6 +1006,9 @@ static bool psmouse_do_detect(int (*detect)(struct psmouse *, bool),
> if (set_properties)
> psmouse_apply_defaults(psmouse);
>
> + if (!detect)
> + return false;

There are no protocols that do not define detect() method, so this
condition is not possible.

> +
> return detect(psmouse, set_properties) == 0;
> }
>

Thanks.

--
Dmitry