Avoid creating before-buffer pointer. Bug 2145

Found by: ASAN / <ago@gentoo.org>

diff --git a/src/src/log.c b/src/src/log.c
index ddd71377e2f75bb335db55a2e37948af10b32e15..62ee629b00320c23e8abec7ea3cbeff825033c2a 100644 (file)
--- a/src/src/log.c
+++ b/src/src/log.c
@@ -391,7 +391,7 @@ it gets statted to see if it has been cycled. With a datestamp, the datestamp
 will be compared. The static slot for saving it is the same size as buffer,
 and the text has been checked above to fit, so this use of strcpy() is OK. */
 
-if (type == lt_main)
+if (type == lt_main && string_datestamp_offset >= 0)
   {
   Ustrcpy(mainlog_name, buffer);
   mainlog_datestamp = mainlog_name + string_datestamp_offset;
@@ -399,7 +399,7 @@ if (type == lt_main)
 
 /* Ditto for the reject log */
 
-else if (type == lt_reject)
+else if (type == lt_reject && string_datestamp_offset >= 0)
   {
   Ustrcpy(rejectlog_name, buffer);
   rejectlog_datestamp = rejectlog_name + string_datestamp_offset;
@@ -1000,7 +1000,7 @@ if (  flags & LOG_MAIN
     operation. This happens at midnight, at which point we want to roll over
     the file. Closing it has the desired effect. */
 
-    if (mainlog_datestamp != NULL)
+    if (mainlog_datestamp)
       {
       uschar *nowstamp = tod_stamp(string_datestamp_type);
       if (Ustrncmp (mainlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)