[U-Boot] [PATCH RESEND v6] usb: gadget: avoid variable name clipping in cb_getvar

Marek Vasut marex at denx.de
Mon Apr 3 13:24:41 UTC 2017


On 04/03/2017 03:09 PM, nicolas.le.bayon at st.com wrote:
> From: Nicolas Le Bayon <nlebayon at gmail.com>
> 
> Instead of using a fixed-size array to store variable name, preferring a
> dynamic allocation treats correctly all variable name lengths.
> Variable names are growing through releases and features. By this way, name
> clipping is prevented.
> 
> Signed-off-by: Nicolas Le Bayon <nlebayon at gmail.com>
> Reviewed-by: Marek Vasut <marex at denx.de>
> Acked-by: Lukasz Majewski <lukma at denx.de>

So I received two patches which are the same, why?

> ---
> 
> Changes in v2:
>  - instead of using a bigger fixed size, use malloc to fit with size needs
> Changes in v3:
>  - v2 was an error (intermediate version), so propose a complete one
> Changes in v4:
>  - be more explicit and detailed in label and description fields
>  - remove intermediate variable only used one time
>  - be more explicit in error message
>  - fix indent issue
> Changes in v5:
>  - drop an unuseful error() call
> Changes in v6:
>  - add Marek review approval
> 
>  drivers/usb/gadget/f_fastboot.c | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/gadget/f_fastboot.c b/drivers/usb/gadget/f_fastboot.c
> index 2160b1c..7cd6d24 100644
> --- a/drivers/usb/gadget/f_fastboot.c
> +++ b/drivers/usb/gadget/f_fastboot.c
> @@ -432,9 +432,15 @@ static void cb_getvar(struct usb_ep *ep, struct usb_request *req)
>  		else
>  			strcpy(response, "FAILValue not set");
>  	} else {
> -		char envstr[32];
> +		char *envstr;
>  
> -		snprintf(envstr, sizeof(envstr) - 1, "fastboot.%s", cmd);
> +		envstr = malloc(strlen("fastboot.") + strlen(cmd) + 1);
> +		if (!envstr) {
> +			fastboot_tx_write_str("FAILmalloc error");
> +			return;
> +		}
> +
> +		sprintf(envstr, "fastboot.%s", cmd);
>  		s = getenv(envstr);
>  		if (s) {
>  			strncat(response, s, chars_left);
> @@ -442,6 +448,8 @@ static void cb_getvar(struct usb_ep *ep, struct usb_request *req)
>  			printf("WARNING: unknown variable: %s\n", cmd);
>  			strcpy(response, "FAILVariable not implemented");
>  		}
> +
> +		free(envstr);
>  	}
>  	fastboot_tx_write_str(response);
>  }
> 


-- 
Best regards,
Marek Vasut


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