client: avoid reading clock after sending request

If chronyc sent a request which caused chronyd to step the clock (e.g.
makestep, settime) and the second reading of the clock before calling
select() to wait for a response happened after the clock was stepped, a
new request could be sent immediately and chronyd would process the same
command twice. If the second request failed (e.g. a settime request too
close to the first request), chronyc would report an error.

Change the submit_request() function to read the clock only once per
select() to wait for the first response even when the clock was stepped.
This commit is contained in:
Miroslav Lichvar 2017-12-12 11:03:04 +01:00
parent de8708f331
commit 6863e43269

View file

@ -1347,15 +1347,15 @@ submit_request(CMD_Request *request, CMD_Reply *reply)
new_attempt = 1;
do {
if (gettimeofday(&tv, NULL))
return 0;
if (new_attempt) {
new_attempt = 0;
if (n_attempts > max_retries)
return 0;
if (gettimeofday(&tv, NULL))
return 0;
UTI_TimevalToTimespec(&tv, &ts_start);
UTI_GetRandomBytes(&request->sequence, sizeof (request->sequence));
@ -1383,9 +1383,6 @@ submit_request(CMD_Request *request, CMD_Reply *reply)
DEBUG_LOG("Sent %d bytes", command_length);
}
if (gettimeofday(&tv, NULL))
return 0;
UTI_TimevalToTimespec(&tv, &ts_now);
/* Check if the clock wasn't stepped back */