httpd patterns double free

[Alexander Schrijver]

I ran into this issue when setting up my public_html folder using this 
configuration.

prefork 2

server "default" {
   listen on * port 80

   location match "/~*" {
      root "/users"
   }
}

types {
   text/css                css
   text/html               html htm
   text/txt                txt
   image/gif               gif
   image/jpeg              jpeg jpg
   image/png               png
   application/javascript  js
   application/xml         xml
}

The patch below fixed it for me. (server_close_http calls str_match_free and
server_close_http can be called more than once.)

Index: patterns.c
===================================================================
RCS file: /backup/mirrors/cvsync/src/usr.sbin/httpd/patterns.c,v
retrieving revision 1.4
diff -u -p -u -r1.4 patterns.c
--- patterns.c  18 Aug 2015 08:26:39 -0000      1.4
+++ patterns.c  11 Feb 2016 14:45:55 -0000
@@ -708,5 +708,6 @@ str_match_free(struct str_match *m)
        for (i = 0; i < m->sm_nmatch; i++)
                free(m->sm_match[i]);
        free(m->sm_match);
+       m->sm_match = NULL;
        m->sm_nmatch = 0;
 }