This as been raised on users@.

---------- Forwarded message ----------
From: Yann Ylavic <ylavic....@gmail.com>
Date: Tue, May 12, 2015 at 10:09 AM

On Mon, May 11, 2015 at 10:54 PM, Michel Stam <mic...@reverze.net> wrote:
>
> I was tinkering over the weekend with mod_authz_dbd and mysql, and i could 
> not get a RequireAny/RequireAll to match on multiple Require dbd-group 
> statements. It would always match only the last result from the query, but 
> once for every row in the resultset.
>
> Example:
>         <LocationMatch "/(?<name>[^/]+)/">
>                 <RequireAny>
>                         Require         user %{env:MATCH_NAME}
>                         Require         dbd-group %{env:MATCH_NAME}
>                         Require         dbd-group Administrators
>                 </RequireAny>
>         </LocationMatch>
>
> After some searching, it appeared to me to be a regression of this:
> https://bz.apache.org/bugzilla/show_bug.cgi?id=46421

The fix mentioned there is about APR's dbd (mysql) code but has never
been pushed to a release (the bugzilla report is still open).
As already discussed in [1] (with a simililar fix for mod_authn_dbd in
[2]), I don't think it should be addressed in APR though (but in httpd
as you and the OP of bugzilla #46421 proposed).

There also seems to be other misuses of apr_dbd_get_entry() returned
values in httpd, I'll start a thread on the dev@ mailing-list and
propose a fix.

[1] http://www.mail-archive.com/dev@apr.apache.org/msg26024.html
[2] http://svn.apache.org/r1663647

---------- End of forwarded message ----------

The issue is that apr_dbd_get_row()'s entries (usually pointed to by
apr_dbd_get_entry(), depending on dbd though) get destroyed whenever
apr_dbd_get_row() returns -1 (no more rows in iterative mode).

This seem to be the case for several dbd systems implemented in APR,
so I think we should take care of the entries' lifetime when used
after an apr_dbd_get_row() loop.
Thus, I think the attached patch should be applied, thoughts?

PS: there are also APR dbd systems where the entries are duplicated on
the apr_dbd_results' pool, so APR is not really consistent...
Index: modules/aaa/mod_authz_dbd.c
===================================================================
--- modules/aaa/mod_authz_dbd.c	(revision 1678763)
+++ modules/aaa/mod_authz_dbd.c	(working copy)
@@ -174,7 +174,9 @@ static int authz_dbd_login(request_rec *r, authz_d
                           action, r->user, message?message:noerror);
                 }
                 else if (newuri == NULL) {
-                    newuri = apr_dbd_get_entry(dbd->driver, row, 0);
+                    newuri =
+                        apr_pstrdup(r->pool,
+                                    apr_dbd_get_entry(dbd->driver, row, 0));
                 }
                 /* we can't break out here or row won't get cleaned up */
             }
@@ -204,7 +206,6 @@ static int authz_dbd_group_query(request_rec *r, a
     apr_dbd_prepared_t *query;
     apr_dbd_results_t *res = NULL;
     apr_dbd_row_t *row = NULL;
-    const char **group;
 
     if (cfg->query == NULL) {
         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01649)
@@ -224,8 +225,9 @@ static int authz_dbd_group_query(request_rec *r, a
              rv != -1;
              rv = apr_dbd_get_row(dbd->driver, r->pool, res, &row, -1)) {
             if (rv == 0) {
-                group = apr_array_push(groups);
-                *group = apr_dbd_get_entry(dbd->driver, row, 0);
+                APR_ARRAY_PUSH(groups, const char *) =
+                    apr_pstrdup(r->pool,
+                                apr_dbd_get_entry(dbd->driver, row, 0));
             }
             else {
                 message = apr_dbd_error(dbd->driver, dbd->handle, rv);
Index: modules/mappers/mod_rewrite.c
===================================================================
--- modules/mappers/mod_rewrite.c	(revision 1678763)
+++ modules/mappers/mod_rewrite.c	(working copy)
@@ -1384,12 +1384,14 @@ static char *lookup_map_dbd(request_rec *r, char *
     while ((rv = apr_dbd_get_row(db->driver, r->pool, res, &row, -1)) == 0) {
         ++n;
         if (ret == NULL) {
-            ret = apr_dbd_get_entry(db->driver, row, 0);
+            ret = apr_pstrdup(r->pool,
+                              apr_dbd_get_entry(db->driver, row, 0));
         }
         else {
             /* randomise crudely amongst multiple results */
             if ((double)rand() < (double)RAND_MAX/(double)n) {
-                ret = apr_dbd_get_entry(db->driver, row, 0);
+                ret = apr_pstrdup(r->pool,
+                                  apr_dbd_get_entry(db->driver, row, 0));
             }
         }
     }
@@ -1402,11 +1404,11 @@ static char *lookup_map_dbd(request_rec *r, char *
     case 0:
         return NULL;
     case 1:
-        return apr_pstrdup(r->pool, ret);
+        return ret;
     default:
         /* what's a fair rewritelog level for this? */
         rewritelog((r, 3, NULL, "Multiple values found for %s", key));
-        return apr_pstrdup(r->pool, ret);
+        return ret;
     }
 }
 
Index: modules/session/mod_session_dbd.c
===================================================================
--- modules/session/mod_session_dbd.c	(revision 1678763)
+++ modules/session/mod_session_dbd.c	(working copy)
@@ -138,7 +138,8 @@ static apr_status_t dbd_load(request_rec * r, cons
             return APR_EGENERAL;
         }
         if (*val == NULL) {
-            *val = apr_dbd_get_entry(dbd->driver, row, 0);
+            *val = apr_pstrdup(r->pool,
+                               apr_dbd_get_entry(dbd->driver, row, 0));
         }
         /* we can't break out here or row won't get cleaned up */
     }

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