philip's inet tcp fix.

diff --git a/servers/inet/generic/tcp_send.c b/servers/inet/generic/tcp_send.c
index 793cbcd0b02867478557852855cd0fcaec3c073c..a10cf8aa52afb70244ec7ea172af8c8e6d13b829 100644 (file)
--- a/servers/inet/generic/tcp_send.c
+++ b/servers/inet/generic/tcp_send.c
@@ -540,7 +540,7 @@ u16_t new_win;
        acc_t *pack;
        clock_t retrans_time, curr_time, rtt, artt, drtt, srtt;
        u32_t queue_lo, queue_hi;
-       u16_t mss, cthresh;
+       u16_t mss, cthresh, new_cthresh;
        unsigned window;
 
        DBLOCK(0x10, printf("tcp_release_retrans, conn[%d]: ack %lu, win %u\n",
@@ -640,9 +640,11 @@ u16_t new_win;
        cthresh= tcp_conn->tc_snd_cthresh;
        if (window > cthresh)
        {
-               cthresh += tcp_conn->tc_snd_cinc;
-               tcp_conn->tc_snd_cthresh= cthresh;
-               window= cthresh;
+               new_cthresh= cthresh + tcp_conn->tc_snd_cinc;
+               if (new_cthresh < cthresh)
+                       new_cthresh= cthresh;           /* overflow */
+               tcp_conn->tc_snd_cthresh= new_cthresh;
+               window= new_cthresh;
        }
 
        /* If the window is larger than the window advertised by the