[nginx] Upstream: fixed unexpected inheritance into limit_except...

[Maxim Dounin]

details:   http://hg.nginx.org/nginx/rev/cd2abf7e7740
branches:  
changeset: 5938:cd2abf7e7740
user:      Maxim Dounin <mdounin at mdounin.ru>
date:      Tue Dec 09 18:22:31 2014 +0300
description:
Upstream: fixed unexpected inheritance into limit_except blocks.

The proxy_pass directive and other handlers are not expected to be inherited
into nested locations, but there is a special code to inherit upstream
handlers into limit_except blocks, as well as a configuration into if{}
blocks.  This caused incorrect behaviour in configurations with nested
locations and limit_except blocks, like this:

    location / {
        proxy_pass http://u;

        location /inner/ {
            # no proxy_pass here

            limit_except GET {
                # nothing
            }
        }
    }

In such a configuration the limit_except block inside "location /inner/"
unexpectedly used proxy_pass defined in "location /", while it shouldn't.
Fix is to avoid inheritance of conf->upstream.upstream (and
conf->proxy_lengths) into locations which don't have noname flag.

diffstat:

 src/http/modules/ngx_http_fastcgi_module.c |  15 +++++++++------
 src/http/modules/ngx_http_proxy_module.c   |  17 ++++++++++-------
 src/http/modules/ngx_http_scgi_module.c    |  15 +++++++++------
 src/http/modules/ngx_http_uwsgi_module.c   |  15 +++++++++------
 4 files changed, 37 insertions(+), 25 deletions(-)

diffs (126 lines):

diff --git a/src/http/modules/ngx_http_fastcgi_module.c b/src/http/modules/ngx_http_fastcgi_module.c
--- a/src/http/modules/ngx_http_fastcgi_module.c
+++ b/src/http/modules/ngx_http_fastcgi_module.c
@@ -2697,17 +2697,20 @@ ngx_http_fastcgi_merge_loc_conf(ngx_conf
         return NGX_CONF_ERROR;
     }
 
-    if (conf->upstream.upstream == NULL && conf->fastcgi_lengths == NULL) {
+    clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
+
+    if (clcf->noname
+        && conf->upstream.upstream == NULL && conf->fastcgi_lengths == NULL)
+    {
         conf->upstream.upstream = prev->upstream.upstream;
         conf->fastcgi_lengths = prev->fastcgi_lengths;
         conf->fastcgi_values = prev->fastcgi_values;
     }
 
-    if (conf->upstream.upstream || conf->fastcgi_lengths) {
-        clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
-        if (clcf->handler == NULL && clcf->lmt_excpt) {
-            clcf->handler = ngx_http_fastcgi_handler;
-        }
+    if (clcf->lmt_excpt && clcf->handler == NULL
+        && (conf->upstream.upstream || conf->fastcgi_lengths))
+    {
+        clcf->handler = ngx_http_fastcgi_handler;
     }
 
 #if (NGX_PCRE)
diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c
--- a/src/http/modules/ngx_http_proxy_module.c
+++ b/src/http/modules/ngx_http_proxy_module.c
@@ -2991,7 +2991,11 @@ ngx_http_proxy_merge_loc_conf(ngx_conf_t
         return NGX_CONF_ERROR;
     }
 
-    if (conf->upstream.upstream == NULL && conf->proxy_lengths == NULL) {
+    clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
+
+    if (clcf->noname
+        && conf->upstream.upstream == NULL && conf->proxy_lengths == NULL)
+    {
         conf->upstream.upstream = prev->upstream.upstream;
         conf->vars = prev->vars;
 
@@ -3003,12 +3007,11 @@ ngx_http_proxy_merge_loc_conf(ngx_conf_t
 #endif
     }
 
-    if (conf->upstream.upstream || conf->proxy_lengths) {
-        clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
-        if (clcf->handler == NULL && clcf->lmt_excpt) {
-            clcf->handler = ngx_http_proxy_handler;
-            conf->location = prev->location;
-        }
+    if (clcf->lmt_excpt && clcf->handler == NULL
+        && (conf->upstream.upstream || conf->proxy_lengths))
+    {
+        clcf->handler = ngx_http_proxy_handler;
+        conf->location = prev->location;
     }
 
     if (conf->body_source.data == NULL) {
diff --git a/src/http/modules/ngx_http_scgi_module.c b/src/http/modules/ngx_http_scgi_module.c
--- a/src/http/modules/ngx_http_scgi_module.c
+++ b/src/http/modules/ngx_http_scgi_module.c
@@ -1443,17 +1443,20 @@ ngx_http_scgi_merge_loc_conf(ngx_conf_t 
         return NGX_CONF_ERROR;
     }
 
-    if (conf->upstream.upstream == NULL && conf->scgi_lengths == NULL) {
+    clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
+
+    if (clcf->noname
+        && conf->upstream.upstream == NULL && conf->scgi_lengths == NULL)
+    {
         conf->upstream.upstream = prev->upstream.upstream;
         conf->scgi_lengths = prev->scgi_lengths;
         conf->scgi_values = prev->scgi_values;
     }
 
-    if (conf->upstream.upstream || conf->scgi_lengths) {
-        clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
-        if (clcf->handler == NULL && clcf->lmt_excpt) {
-            clcf->handler = ngx_http_scgi_handler;
-        }
+    if (clcf->lmt_excpt && clcf->handler == NULL
+        && (conf->upstream.upstream || conf->scgi_lengths))
+    {
+        clcf->handler = ngx_http_scgi_handler;
     }
 
     if (conf->params_source == NULL) {
diff --git a/src/http/modules/ngx_http_uwsgi_module.c b/src/http/modules/ngx_http_uwsgi_module.c
--- a/src/http/modules/ngx_http_uwsgi_module.c
+++ b/src/http/modules/ngx_http_uwsgi_module.c
@@ -1698,7 +1698,11 @@ ngx_http_uwsgi_merge_loc_conf(ngx_conf_t
         return NGX_CONF_ERROR;
     }
 
-    if (conf->upstream.upstream == NULL && conf->uwsgi_lengths == NULL) {
+    clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
+
+    if (clcf->noname
+        && conf->upstream.upstream == NULL && conf->uwsgi_lengths == NULL)
+    {
         conf->upstream.upstream = prev->upstream.upstream;
 
         conf->uwsgi_lengths = prev->uwsgi_lengths;
@@ -1709,11 +1713,10 @@ ngx_http_uwsgi_merge_loc_conf(ngx_conf_t
 #endif
     }
 
-    if (conf->upstream.upstream || conf->uwsgi_lengths) {
-        clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
-        if (clcf->handler == NULL && clcf->lmt_excpt) {
-            clcf->handler = ngx_http_uwsgi_handler;
-        }
+    if (clcf->lmt_excpt && clcf->handler == NULL
+        && (conf->upstream.upstream || conf->uwsgi_lengths))
+    {
+        clcf->handler = ngx_http_uwsgi_handler;
     }
 
     ngx_conf_merge_uint_value(conf->modifier1, prev->modifier1, 0);