httpd/backport-002-CVE-2021-44224.patch

From a0521d289ae14e4ac004811dc1ef91b3e118a2f6 Mon Sep 17 00:00:00 2001
From: Stefan Eissing <icing@apache.org>
Date: Thu, 16 Dec 2021 11:23:49 +0000
Subject: [PATCH] Merge of r1895981,r1895986 from trunk:

  *) mod_proxy: Don't prevent forwarding URIs w/ no hostname.
                (fix for r1895955 already in 2.4.x)



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1896044 13f79535-47bb-0310-9956-ffa450edef68
---
 modules/proxy/mod_proxy.c  |  5 +++--
 modules/proxy/mod_proxy.h  |  1 +
 modules/proxy/proxy_util.c | 22 ++++++++++++----------
 3 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/modules/proxy/mod_proxy.c b/modules/proxy/mod_proxy.c
index 85d7ce2e6c1..f8a4db68892 100644
--- a/modules/proxy/mod_proxy.c
+++ b/modules/proxy/mod_proxy.c
@@ -775,9 +775,10 @@ static int proxy_detect(request_rec *r)
 
     /* Ick... msvc (perhaps others) promotes ternary short results to int */
 
-    if (conf->req && r->parsed_uri.scheme && r->parsed_uri.hostname) {
+    if (conf->req && r->parsed_uri.scheme) {
         /* but it might be something vhosted */
-        if (ap_cstr_casecmp(r->parsed_uri.scheme, ap_http_scheme(r)) != 0
+        if (!r->parsed_uri.hostname
+            || ap_cstr_casecmp(r->parsed_uri.scheme, ap_http_scheme(r)) != 0
             || !ap_matches_request_vhost(r, r->parsed_uri.hostname,
                                          (apr_port_t)(r->parsed_uri.port_str
                                                       ? r->parsed_uri.port
diff --git a/modules/proxy/mod_proxy.h b/modules/proxy/mod_proxy.h
index 35acc49a4a3..be5b3a85394 100644
--- a/modules/proxy/mod_proxy.h
+++ b/modules/proxy/mod_proxy.h
@@ -750,6 +750,7 @@ PROXY_DECLARE(int) ap_proxy_worker_can_upgrade(apr_pool_t *p,
 #define AP_PROXY_WORKER_IS_PREFIX   (1u << 0)
 #define AP_PROXY_WORKER_IS_MATCH    (1u << 1)
 #define AP_PROXY_WORKER_IS_MALLOCED (1u << 2)
+#define AP_PROXY_WORKER_NO_UDS      (1u << 3)
 
 /**
  * Get the worker from proxy configuration, looking for either PREFIXED or
diff --git a/modules/proxy/proxy_util.c b/modules/proxy/proxy_util.c
index b4f6dcfadc6..8cb315d9103 100644
--- a/modules/proxy/proxy_util.c
+++ b/modules/proxy/proxy_util.c
@@ -1741,9 +1741,11 @@ PROXY_DECLARE(proxy_worker *) ap_proxy_get_worker_ex(apr_pool_t *p,
         return NULL;
     }
 
-    url = ap_proxy_de_socketfy(p, url);
-    if (!url) {
-        return NULL;
+    if (!(mask & AP_PROXY_WORKER_NO_UDS)) {
+        url = ap_proxy_de_socketfy(p, url);
+        if (!url) {
+            return NULL;
+        }
     }
 
     c = ap_strchr_c(url, ':');
@@ -2326,22 +2328,22 @@ PROXY_DECLARE(int) ap_proxy_pre_request(proxy_worker **worker,
 
     access_status = proxy_run_pre_request(worker, balancer, r, conf, url);
     if (access_status == DECLINED && *balancer == NULL) {
-        *worker = ap_proxy_get_worker(r->pool, NULL, conf, *url);
+        const int forward = (r->proxyreq == PROXYREQ_PROXY);
+        *worker = ap_proxy_get_worker_ex(r->pool, NULL, conf, *url,
+                                         forward ? AP_PROXY_WORKER_NO_UDS : 0);
         if (*worker) {
             ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
                           "%s: found worker %s for %s",
                           (*worker)->s->scheme, (*worker)->s->name, *url);
-            *balancer = NULL;
-            if (!fix_uds_filename(r, url)) {
+            if (!forward && !fix_uds_filename(r, url)) {
                 return HTTP_INTERNAL_SERVER_ERROR;
             }
             access_status = OK;
         }
-        else if (r->proxyreq == PROXYREQ_PROXY) {
+        else if (forward) {
             if (conf->forward) {
                 ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
                               "*: found forward proxy worker for %s", *url);
-                *balancer = NULL;
                 *worker = conf->forward;
                 access_status = OK;
                 /*
@@ -2355,8 +2357,8 @@ PROXY_DECLARE(int) ap_proxy_pre_request(proxy_worker **worker,
         else if (r->proxyreq == PROXYREQ_REVERSE) {
             if (conf->reverse) {
                 ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
-                              "*: using default reverse proxy worker for %s (no keepalive)", *url);
-                *balancer = NULL;
+                              "*: using default reverse proxy worker for %s "
+                              "(no keepalive)", *url);
                 *worker = conf->reverse;
                 access_status = OK;
                 /*