Index: src/libmtp.c
===================================================================
--- src/libmtp.c	(revision 148643)
+++ src/libmtp.c	(working copy)
@@ -1728,6 +1728,10 @@
   int start = 0;
   int end = 0;
 
+  /* NULL on Canon A70 */
+  if (!desc)
+    return;
+
   /* descriptors are divided by semicolons */
   while (end < strlen(desc)) {
     /* Skip past initial whitespace */