Slice filter: prevented slice redirection (ticket #1219).

When a slice subrequest was redirected to a new location, its context was lost.
After its completion, a new slice subrequest for the same slice was created.
This could lead to infinite loop.  Now the slice module makes sure each slice
subrequest starts output with the slice context available.

1 files changed, 11 insertions, 1 deletions

diff --git a/src/http/modules/ngx_http_slice_filter_module.c b/src/http/modules/ngx_http_slice_filter_module.c
index a3b2dde6e..77583429f 100644
--- a/src/http/modules/ngx_http_slice_filter_module.c
+++ b/src/http/modules/ngx_http_slice_filter_module.c
@@ -20,7 +20,8 @@ typedef struct {
     off_t                end;
     ngx_str_t            range;
     ngx_str_t            etag;
-    ngx_uint_t           last;  /* unsigned  last:1; */
+    unsigned             last:1;
+    unsigned             active:1;
     ngx_http_request_t  *sr;
 } ngx_http_slice_ctx_t;
 
@@ -170,6 +171,7 @@ ngx_http_slice_header_filter(ngx_http_request_t *r)
     }
 
     ctx->start = end;
+    ctx->active = 1;
 
     r->headers_out.status = NGX_HTTP_OK;
     r->headers_out.status_line.len = 0;
@@ -238,6 +240,12 @@ ngx_http_slice_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
         return rc;
     }
 
+    if (!ctx->active) {
+        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                      "missing slice response");
+        return NGX_ERROR;
+    }
+
     if (ctx->start >= ctx->end) {
         ngx_http_set_ctx(r, NULL, ngx_http_slice_filter_module);
         ngx_http_send_special(r, NGX_HTTP_LAST);
@@ -263,6 +271,8 @@ ngx_http_slice_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
                                  ctx->start + (off_t) slcf->size - 1)
                      - ctx->range.data;
 
+    ctx->active = 0;
+
     ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                    "http slice subrequest: \"%V\"", &ctx->range);