Don't call memchr(foo,'\0',-1) even if it has no ill effects.

Thanks to George Kadianakis <desnacked@riseup.net> for the report.

ChangeLog

+2012-08-17
+
+	* src/message.c: Don't call memchr(foo,'\0',-1) even if it has
+	no ill effects.  Thanks to George Kadianakis
+	<desnacked@riseup.net> for the report.
+
 2012-07-20
 
 	* src/message.c, src/instag.c, toolkit/parse.c, src/sm.c,

src/message.c

@@ -1350,7 +1350,7 @@ int otrl_message_receiving(OtrlUserState us, const OtrlMessageAppOps *ops,
 
 		    tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP1Q);
 		    if (tlv) {
-			if (nextMsg == OTRL_SMP_EXPECT1) {
+			if (nextMsg == OTRL_SMP_EXPECT1 && tlv->len > 0) {
 			    /* We can only do the verification half now.
 			     * We must wait for the secret to be entered
 			     * to continue. */