md: fix input truncation in safe_delay_store()

safe_delay_store() currently truncates the last character of input since
it tells strlcpy that the buffer can only hold 'len' characters, off by
one.  sysfs already null terminates the buffer, so just increase the
last argument to strlcpy.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

drivers/md/md.c

@@ -2394,12 +2394,11 @@ safe_delay_store(mddev_t *mddev, const char *cbuf, size_t len)
 	int i;
 	unsigned long msec;
 	char buf[30];
-	char *e;
+
 	/* remove a period, and count digits after it */
 	if (len >= sizeof(buf))
 		return -EINVAL;
-	strlcpy(buf, cbuf, len);
-	buf[len] = 0;
+	strlcpy(buf, cbuf, sizeof(buf));
 	for (i=0; i<len; i++) {
 		if (dot) {
 			if (isdigit(buf[i])) {
@@ -2412,8 +2411,7 @@ safe_delay_store(mddev_t *mddev, const char *cbuf, size_t len)
 			buf[i] = 0;
 		}
 	}
-	msec = simple_strtoul(buf, &e, 10);
-	if (e == buf || (*e && *e != '\n'))
+	if (strict_strtoul(buf, 10, &msec) < 0)
 		return -EINVAL;
 	msec = (msec * 1000) / scale;
 	if (msec == 0)