tor

commit e67f4441eb2646368e3e7cb1bcee403667b786f0
parent 8171d9f50f985de743a415ae5bf61b97e91ce8c8
Author: David Goulet <dgoulet@torproject.org>
Date:   Tue,  7 Nov 2017 11:14:45 -0500

Add a safe guard to avoid using a zeroed voting schedule

dirvote_get_next_valid_after_time() is the only public function that uses the
voting schedule outside of the dirvote subsystem so if it is zeroed,
recalculate its timing if we can that is if a consensus exists.

Part of #24161

Signed-off-by: David Goulet <dgoulet@torproject.org>

Diffstat:
M
src/or/dirvote.c
 | 
7
+++++++

1 file changed, 7 insertions(+), 0 deletions(-)
diff --git a/src/or/dirvote.c b/src/or/dirvote.c
@@ -2859,6 +2859,13 @@ static voting_schedule_t voting_schedule;
 time_t
 dirvote_get_next_valid_after_time(void)
 {
+  /* This is a safe guard in order to make sure that the voting schedule
+   * static object is at least initialized. Using this function with a zeroed
+   * voting schedule can lead to bugs. */
+  if (tor_mem_is_zero((const char *) &voting_schedule,
+                      sizeof(voting_schedule))) {
+    dirvote_recalculate_timing(get_options(), time(NULL));
+  }
   return voting_schedule.interval_starts;
 }