From 2ffcfb9b45262271019d1751cafc895c3dae8f0e Mon Sep 17 00:00:00 2001
From: Robert Milasan <rmilasan@suse.com>
Date: Sun, 10 Feb 2013 11:00:20 +0100
Subject: [PATCH] usb_id: some strange devices have a very bogus or strange serial
 numer, making a mess in /dev/disk/by-id. Let's check if the
 serial number is a valid, otherwise don't use it.

---
 src/udev/udev-builtin-usb_id.c |   23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

Index: systemd-195/src/udev/udev-builtin-usb_id.c
===================================================================
--- systemd-195.orig/src/udev/udev-builtin-usb_id.c
+++ systemd-195/src/udev/udev-builtin-usb_id.c
@@ -23,6 +23,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <string.h>
 #include <ctype.h>
@@ -31,6 +32,26 @@
 
 #include "udev.h"
 
+static bool valid_string(const char *str)
+{
+        const char *s;
+
+        if (!str)
+            return false;
+
+        for (s = str; *s != '\0'; s++) {
+             if ((*s >= 'a' && *s <= 'z') ||
+                 (*s >= 'A' && *s <= 'Z') ||
+                 (*s >= '0' && *s <= '9') ||
+                  *s == '-' || *s == '_')
+                    continue;
+              else
+                    return false;
+        }
+
+        return true;
+}
+
 static void set_usb_iftype(char *to, int if_class_num, size_t len)
 {
         const char *type = "generic";
@@ -428,10 +449,10 @@ fallback:
         }
 
         if (serial_str[0] == '\0') {
-                const char *usb_serial;
+                const char *usb_serial = NULL;
 
                 usb_serial = udev_device_get_sysattr_value(dev_usb, "serial");
-                if (usb_serial) {
+                if (valid_string(usb_serial)) {
                         util_replace_whitespace(usb_serial, serial_str, sizeof(serial_str)-1);
                         util_replace_chars(serial_str, NULL);
                 }