Re: [PATCH] Fix USB Type C hub crash in typec_altmode_update_active

[Zwane Mwaikambo]

On Sat, 25 Jul 2020, Zwane Mwaikambo wrote:

> diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> index d0c63afaf..30d0857e4 100644
> --- a/drivers/usb/typec/ucsi/ucsi.c
> +++ b/drivers/usb/typec/ucsi/ucsi.c
> @@ -218,9 +218,12 @@ void ucsi_altmode_update_active(struct ucsi_connector *con)
>  	if (cur < UCSI_MAX_ALTMODES)
>  		altmode = typec_altmode_get_partner(con->port_altmode[cur]);
>  
> -	for (i = 0; con->partner_altmode[i]; i++)
> -		typec_altmode_update_active(con->partner_altmode[i],
> -					    con->partner_altmode[i] == altmode);
> +	for (i = 0; i < UCSI_MAX_ALTMODES; i++) {
> +        if (con->partner_altmode[i]) {
> +		    typec_altmode_update_active(con->partner_altmode[i],
> +			                            con->partner_altmode[i] == altmode);
> +        }
> +    }
>  }
>  
>  static u8 ucsi_altmode_next_mode(struct typec_altmode **alt, u16 svid)
> 

Previous patch had whitespace issues and i cleaned it up for coding style 
reasons, patch is against 5.8.0-rc6

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index d0c63afaf..30e811fde 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -218,9 +218,10 @@ void ucsi_altmode_update_active(struct ucsi_connector *con)
 	if (cur < UCSI_MAX_ALTMODES)
 		altmode = typec_altmode_get_partner(con->port_altmode[cur]);
 
-	for (i = 0; con->partner_altmode[i]; i++)
-		typec_altmode_update_active(con->partner_altmode[i],
-					    con->partner_altmode[i] == altmode);
+	for (i = 0; i < UCSI_MAX_ALTMODES; i++)
+		if (con->partner_altmode[i])
+			typec_altmode_update_active(con->partner_altmode[i],
+										con->partner_altmode[i] == altmode);
 }
 
 static u8 ucsi_altmode_next_mode(struct typec_altmode **alt, u16 svid)