[PATCH][next] usb: typec: mux: fix an unsigned less than zero check

[PATCH][next] usb: typec: mux: fix an unsigned less than zero check

[Colin King]

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

The checks of a negative nval indicating an error an never be true
as nval is currently a size_t which is of course unsigned and hence
never less than zero. Fix this by making nval an int.

Detected by CoverityScan, CID#1476863 ("Unsigned compared against 0) 
and CID#1476948 ("Loop bound")

Fixes: 96a6d031ca99 ("usb: typec: mux: Find the muxes by also matching against the device node")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/usb/typec/mux.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/usb/typec/mux.c b/drivers/usb/typec/mux.c
index b94e2920eb38..64d2ed3fecb8 100644
--- a/drivers/usb/typec/mux.c
+++ b/drivers/usb/typec/mux.c
@@ -126,10 +126,9 @@ static void *typec_mux_match(struct device_connection *con, int ep, void *data)
 {
 	const struct typec_altmode_desc *desc = data;
 	struct typec_mux *mux;
-	size_t nval;
 	bool match;
 	u16 *val;
-	int i;
+	int i, nval;
 
 	if (!con->fwnode) {
 		list_for_each_entry(mux, &mux_list, entry)
-- 
2.20.1

Re: [PATCH][next] usb: typec: mux: fix an unsigned less than zero check

[Heikki Krogerus]

On Tue, Feb 19, 2019 at 03:19:18PM +0000, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> The checks of a negative nval indicating an error an never be true
> as nval is currently a size_t which is of course unsigned and hence
> never less than zero. Fix this by making nval an int.
> 
> Detected by CoverityScan, CID#1476863 ("Unsigned compared against 0) 
> and CID#1476948 ("Loop bound")
> 
> Fixes: 96a6d031ca99 ("usb: typec: mux: Find the muxes by also matching against the device node")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
>  drivers/usb/typec/mux.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/typec/mux.c b/drivers/usb/typec/mux.c
> index b94e2920eb38..64d2ed3fecb8 100644
> --- a/drivers/usb/typec/mux.c
> +++ b/drivers/usb/typec/mux.c
> @@ -126,10 +126,9 @@ static void *typec_mux_match(struct device_connection *con, int ep, void *data)
>  {
>  	const struct typec_altmode_desc *desc = data;
>  	struct typec_mux *mux;
> -	size_t nval;
>  	bool match;
>  	u16 *val;
> -	int i;
> +	int i, nval;
>  
>  	if (!con->fwnode) {
>  		list_for_each_entry(mux, &mux_list, entry)
> -- 
> 2.20.1

This one has already a fix:
https://lkml.org/lkml/2019/2/19/56

thanks,

-- 
heikki