From: Ondrej Zajicek (work) <santiago@crfreenet.org>
Date: Tue, 1 Nov 2016 10:37:49 +0000 (+0100)
Subject: Log: Fix broken syslog name
X-Git-Tag: v1.6.3~16
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=17fe57d8dcc89aea520788914b252cf49cf060ff;p=thirdparty%2Fbird.git

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.
---

diff --git a/lib/string.h b/lib/string.h
index 9af49b9ee..bf0b7cb07 100644
--- a/lib/string.h
+++ b/lib/string.h
@@ -30,6 +30,15 @@ static inline char *xbasename(const char *str)
   return s ? s+1 : (char *) str;
 }
 
+static inline char *
+xstrdup(const char *c)
+{
+  size_t l = strlen(c) + 1;
+  char *z = xmalloc(l);
+  memcpy(z, c, l);
+  return z;
+}
+
 #define ROUTER_ID_64_LENGTH 23
 
 #endif
diff --git a/sysdep/unix/log.c b/sysdep/unix/log.c
index 1fd644265..b89e6b7a0 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
 }