* What are the values of x, y, and mod when the assertion is hit? 32, -1, 64
* A call stack trace would be nice, i.e. which function was calling modulo_add when the assertion was hit? It's actually being called through the macro CIRC_LIST_PUSH (p->seq_list, SEQ_UNSEEN); #0 packet_id_add (p=0xbffff02c, pin=0xbfffe9bc) at packet_id.c:116 #1 0x0000d628 in openvpn_decrypt (buf=0xbfffea74, work= {capacity = 1596, offset = 56, len = 97, data = 0x7425c ""}, opt=0xbffff014, frame=0xbfffe9e0) at crypto.c:364 #2 0x0000ef54 in test_crypto (co=0xbffff014, frame=0xbfffeef4) at crypto.c:883 #3 0x00019ec0 in test_crypto_thread (arg=0x4a488) at init.c:2635 #4 0x00019f5c in do_test_crypto (o=0xbffff180) at init.c:2667 #5 0x00028884 in main (argc=4, argv=0xbffff844) at openvpn.c:175 * Does the assertion always hit in the test above immediately after packet length=97? Yes. * What is the config file or command line which was used to generate the test?