apache-bug-39311-preforkonly.patch

   1 --- httpd-2.2.24/server/mpm/prefork/prefork.c~  2012-07-27 21:51:57.000000000 +0200
   2 +++ httpd-2.2.24/server/mpm/prefork/prefork.c   2013-04-09 17:58:05.772765411 +0200
   3 @@ -1043,14 +1043,31 @@
   4           * extra child
   5           */
   6          if (pid.pid != -1) {
   7 +            process_score *child_record;
   8              processed_status = ap_process_child_status(&pid, exitwhy, status);
   9 +            child_slot = find_child_by_pid(&pid);
  10              if (processed_status == APEXIT_CHILDFATAL) {
  11 -                mpm_state = AP_MPMQ_STOPPING;
  12 -                return 1;
  13 +                /* fix race condition found in PR 39311
  14 +                * A child created at the same time as a graceful happens
  15 +                * can find the lock missing and create a fatal error.
  16 +                * It is not fatal for the last generation to be in this state.
  17 +                */
  18 +               child_record = ap_get_scoreboard_process(child_slot);
  19 +               if (child_slot < 0
  20 +                   || child_record->generation
  21 +                      == ap_my_generation) {
  22 +                   mpm_state = AP_MPMQ_STOPPING;
  23 +                   return DONE;
  24 +               }
  25 +               else {
  26 +                   ap_log_error(APLOG_MARK, APLOG_WARNING, 0, ap_server_conf,
  27 +                                "Ignoring fatal error in child of previous "
  28 +                                "generation (pid %ld).",
  29 +                                (long)pid.pid);
  30 +               }
  31              }
  32
  33              /* non-fatal death... note that it's gone in the scoreboard. */
  34 -            child_slot = find_child_by_pid(&pid);
  35              if (child_slot >= 0) {
  36                  (void) ap_update_child_status_from_indexes(child_slot, 0, SERVER_DEAD,
  37                                                             (request_rec *) NULL);