[PATCH 01 of 13] Dav: fixed segfault on PUT if body was already read (ticket #238)

[Maxim Dounin]

# HG changeset patch
# User Maxim Dounin <mdounin at mdounin.ru>
# Date 1352393278 -14400
# Node ID c26606971d58dd27df5f72b9fcf90bc883038d76
# Parent  1b2abbd52edc283f69c7513a6cb5406f7913ecae
Dav: fixed segfault on PUT if body was already read (ticket #238).

If request body reading happens with different options it's possible
that there will be no r->request_body->temp_file available (or even
no r->request_body available if body was discarded).  Return internal
server error in this case instead of committing suicide by dereferencing
a null pointer.

diff --git a/src/http/modules/ngx_http_dav_module.c b/src/http/modules/ngx_http_dav_module.c
--- a/src/http/modules/ngx_http_dav_module.c
+++ b/src/http/modules/ngx_http_dav_module.c
@@ -209,6 +209,11 @@ ngx_http_dav_put_handler(ngx_http_reques
     ngx_ext_rename_file_t     ext;
     ngx_http_dav_loc_conf_t  *dlcf;
 
+    if (r->request_body == NULL || r->request_body->temp_file == NULL) {
+        ngx_http_finalize_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
+        return;
+    }
+
     ngx_http_map_uri_to_path(r, &path, &root, 0);
 
     path.len--;