Fix assertion failure in tor_timegm.

Fixes bug 6811.

2 files changed, 6 insertions, 3 deletions

diff --git a/src/or/directory.c b/src/or/directory.c
index 29cf10cea0..975f8910cd 100644
--- a/src/or/directory.c
+++ b/src/or/directory.c
@@ -2493,7 +2493,8 @@ directory_handle_command_get(dir_connection_t *conn, const char *headers,
   if ((header = http_get_header(headers, "If-Modified-Since: "))) {
     struct tm tm;
     if (parse_http_time(header, &tm) == 0) {
-      if_modified_since = tor_timegm(&tm);
+      if (tor_timegm(&tm, &if_modified_since)<0)
+        if_modified_since = 0;
     }
     /* The correct behavior on a malformed If-Modified-Since header is to
      * act as if no If-Modified-Since header had been given. */
diff --git a/src/or/dirvote.c b/src/or/dirvote.c
index ab08fd0200..a557fc782e 100644
--- a/src/or/dirvote.c
+++ b/src/or/dirvote.c
@@ -2536,7 +2536,7 @@ time_t
 dirvote_get_start_of_next_interval(time_t now, int interval)
 {
   struct tm tm;
-  time_t midnight_today;
+  time_t midnight_today=0;
   time_t midnight_tomorrow;
   time_t next;
 
@@ -2545,7 +2545,9 @@ dirvote_get_start_of_next_interval(time_t now, int interval)
   tm.tm_min = 0;
   tm.tm_sec = 0;
 
-  midnight_today = tor_timegm(&tm);
+  if (tor_timegm(&tm, &midnight_today) < 0) {
+    log_warn(LD_BUG, "Ran into an invalid time when trying to find midnight.");
+  }
   midnight_tomorrow = midnight_today + (24*60*60);
 
   next = midnight_today + ((now-midnight_today)/interval + 1)*interval;