Log: Fix broken syslog name

BIRD passed string from configuration to openlog(), which kept it
internally. After reconfiguration the old string was freed, therefore
openlog had invalid copy.

Thanks to Chris Caputo for the original patch.

1 files changed, 11 insertions, 7 deletions

diff --git a/sysdep/unix/log.c b/sysdep/unix/log.c
index 1fd64426..b89e6b7a 100644
--- a/sysdep/unix/log.c
+++ b/sysdep/unix/log.c
@@ -288,18 +288,22 @@ log_switch(int debug, list *l, char *new_syslog_name)
   current_log_list = l;
 
 #ifdef HAVE_SYSLOG
-  char *old_syslog_name = current_syslog_name;
-  current_syslog_name = new_syslog_name;
-
-  if (old_syslog_name && new_syslog_name &&
-      !strcmp(old_syslog_name, new_syslog_name))
+  if (current_syslog_name && new_syslog_name &&
+      !strcmp(current_syslog_name, new_syslog_name))
     return;
 
-  if (old_syslog_name)
+  if (current_syslog_name)
+  {
     closelog();
+    xfree(current_syslog_name);
+    current_syslog_name = NULL;
+  }
 
   if (new_syslog_name)
-    openlog(new_syslog_name, LOG_CONS | LOG_NDELAY, LOG_DAEMON);
+  {
+    current_syslog_name = xstrdup(new_syslog_name);
+    openlog(current_syslog_name, LOG_CONS | LOG_NDELAY, LOG_DAEMON);
+  }
 #endif
 }