[PATCH 4/8] usb: sandbox: Check for string end in copy_to_unicode()

[Andrew Scull <ascull@google.com>]

When copying the string in copy_to_unicode(), check for the null
terminator in each position, not just at the start, to avoid reading
beyond the end of the string.

Signed-off-by: Andrew Scull <ascull@google.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Marek Vasut <marex@denx.de>
---
 drivers/usb/emul/usb-emul-uclass.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/emul/usb-emul-uclass.c b/drivers/usb/emul/usb-emul-uclass.c
index 05f6d3d9e2..b31dc950e3 100644
--- a/drivers/usb/emul/usb-emul-uclass.c
+++ b/drivers/usb/emul/usb-emul-uclass.c
@@ -15,13 +15,12 @@
 static int copy_to_unicode(char *buff, int length, const char *str)
 {
 	int ptr;
-	int i;
 
 	if (length < 2)
 		return 0;
 	buff[1] = USB_DT_STRING;
-	for (ptr = 2, i = 0; ptr + 1 < length && *str; i++, ptr += 2) {
-		buff[ptr] = str[i];
+	for (ptr = 2; ptr + 1 < length && *str; str++, ptr += 2) {
+		buff[ptr] = *str;
 		buff[ptr + 1] = 0;
 	}
 	buff[0] = ptr;
-- 
2.35.1.1094.g7c7d902a7c-goog