diff -up logrotate-3.7.7/config.c.toolarge logrotate-3.7.7/config.c
--- logrotate-3.7.7/config.c.toolarge	2008-11-21 12:57:25.000000000 +0100
+++ logrotate-3.7.7/config.c	2008-11-21 12:57:41.000000000 +0100
@@ -530,6 +530,13 @@ static int readConfigFile(const char *co
 
     length = sb.st_size;
 
+    if (length > 0xffffff) {
+        message(MESS_ERROR, "file %s too large, probably not a config file.\n",
+                configFile);
+        close(fd);
+        return 1;
+    }    
+
     buf = alloca(length + 2);
     if (!buf) {
 	message(MESS_ERROR, "alloca() of %d bytes failed\n", (int) length);