Re: bin/45257: ping(8) prints bogus round-trip times after Year 2038

[Ryo Shimizu <ryo%nerv.org@localhost>]

>Why all the complexity? All you should need is to cast to unsigned when
>assigning.

No. it is not enough.


>@@ -995,7 +995,7 @@
>                       struct tv32 tv32;
> 
>                       (void) memcpy(&tv32, icp->icmp_data, sizeof(tv32));
>-                      tv.tv_sec = ntohl(tv32.tv32_sec);
>+                      tv.tv_sec = (uint32_t)ntohl(tv32.tv32_sec);
>                       tv.tv_usec = ntohl(tv32.tv32_usec);
>                       triptime = diffsec(&last_rx, &tv);
>                       tsum += triptime;


In case of last_rx.tv_sec is over 0x100000000,
diffsec(&last_rx, &tv) returns big value.

e.g.) last_rx.tv_sec = 0x100000005, tv.tv_sec = 0x00000004, result is 
0x100000001.

# date 210602070628.13  # unixtime 0xfffffffd
Sun Feb  7 06:28:13 UTC 2106
# ping localhost
PING localhost (127.0.0.1): 56 data bytes
64 bytes from 127.0.0.1: icmp_seq=0 ttl=255 time=0.019 ms
64 bytes from 127.0.0.1: icmp_seq=1 ttl=255 time=0.026 ms
64 bytes from 127.0.0.1: icmp_seq=2 ttl=255 time=4294967296000.025 ms
64 bytes from 127.0.0.1: icmp_seq=3 ttl=255 time=4294967296000.024 ms
64 bytes from 127.0.0.1: icmp_seq=4 ttl=255 time=4294967296000.027 ms
64 bytes from 127.0.0.1: icmp_seq=5 ttl=255 time=4294967296000.026 ms
^C
----localhost PING Statistics----
6 packets transmitted, 6 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 
0.019/2863311530666.691/4294967296000.027/2217911574655.135 ms

--
ryo shimizu