From: Ondrej Zajicek (work) <santiago@crfreenet.org>
Date: Wed, 25 Nov 2020 14:15:13 +0000 (+0100)
Subject: Log: Fix locking during log reconfiguration
X-Git-Tag: v2.0.8~35
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=62d57b9bdf82cc978f889f0118c8aa19ae999a3d;p=thirdparty%2Fbird.git

Log: Fix locking during log reconfiguration

The log subsystem should be locked earlier, as default_log_list() may
internally manipulate with the current_log_list (if it is also a default
log list).
---

diff --git a/sysdep/unix/log.c b/sysdep/unix/log.c
index 44536cc94..14d18c018 100644
--- a/sysdep/unix/log.c
+++ b/sysdep/unix/log.c
@@ -382,12 +382,12 @@ log_switch(int initial, list *logs, const char *new_syslog_name)
 {
   struct log_config *l;
 
+  /* We should not manipulate with log list when other threads may use it */
+  log_lock();
+
   if (!logs || EMPTY_LIST(*logs))
     logs = default_log_list(initial, &new_syslog_name);
 
-  /* We shouldn't close the logs when other threads may use them */
-  log_lock();
-
   /* Close the logs to avoid pinning them on disk when deleted */
   if (current_log_list)
     WALK_LIST(l, *current_log_list)