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

[Nicolas LE BAYON]

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.

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