[SCSI] zfcp: fix module parameter parsing

From: Heiko Carstens <heiko.carstens@de.ibm.com>

Fixes module parameter parsing for "device" parameter.  The original
module parameter was changed while parsing it.  This corrupted the
output in sysfs (/sys/module/zfcp/parameters/device).
Signed-off-by: Andreas Herrmann <aherrman@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/s390/scsi/zfcp_aux.c

@@ -218,13 +218,20 @@ zfcp_in_els_dbf_event(struct zfcp_adapter *adapter, const char *text,
  * Parse "device=..." parameter string.
  */
 static int __init
-zfcp_device_setup(char *str)
+zfcp_device_setup(char *devstr)
 {
-	char *tmp;
+	char *tmp, *str;
+	size_t len;
 
-	if (!str)
+	if (!devstr)
 		return 0;
 
+	len = strlen(devstr) + 1;
+	str = (char *) kmalloc(len, GFP_KERNEL);
+	if (!str)
+		goto err_out;
+	memcpy(str, devstr, len);
+
 	tmp = strchr(str, ',');
 	if (!tmp)
 		goto err_out;
@@ -241,10 +248,12 @@ zfcp_device_setup(char *str)
 	zfcp_data.init_fcp_lun = simple_strtoull(tmp, &tmp, 0);
 	if (*tmp != '\0')
 		goto err_out;
+	kfree(str);
 	return 1;
 
  err_out:
 	ZFCP_LOG_NORMAL("Parse error for device parameter string %s\n", str);
+	kfree(str);
 	return 0;
 }