[U-Boot] [PATCH v7] usb: gadget: avoid variable name clipping in cb_getvar

[Lukasz Majewski]

On Tue, 9 May 2017 15:58:36 +0000
Nicolas LE BAYON <nicolas.le.bayon at st.com> wrote:

> Hi,
> 
> A kind reminder to look at this patch (already reviewed by Marek and
> acked by Lukasz), and if possible to put it in the next pull list, or
> the one after is timing is too short.

I wanted to add this patch with other ones. Unfortunately those other
patches needed more review, so I postponed the PR.

I will ask Tom to take this one directly.



> 
> Thanks in advance for your time
> 
> Best Regards
> Nicolas
> 
> -----Original Message-----
> From: Nicolas LE BAYON 
> Sent: mardi 25 avril 2017 10:18
> To: Nicolas LE BAYON <nicolas.le.bayon at st.com>; u-boot at lists.denx.de;
> lukma at denx.de; marex at denx.de Cc: nlebayon at gmail.com; Patrice CHOTARD
> <patrice.chotard at st.com>; Jean-philippe ROMAIN
> <jean-philippe.romain at st.com> Subject: [U-Boot][PATCH v7] usb:
> gadget: avoid variable name clipping in cb_getvar
> 
> From: Nicolas Le Bayon <nicolas.le.bayon at st.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 <nicolas.le.bayon at st.com>
> Reviewed-by: Marek Vasut <marex at denx.de>
> Acked-by: Lukasz Majewski <lukma at denx.de>
> ---
> 
> 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
> Changes in v7:
>  - add Lukasz ack 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);
>  }
> --
> 1.9.1
> 




Best regards,

Lukasz Majewski

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