http: compression: Add a missed nxt_http_comp_compress() return check

In nxt_http_comp_compress_static_response() we should check the return
value of the call to nxt_http_comp_compress() in case of error.

Signed-off-by: Andrew Clayton <a.clayton@nginx.com>

Author: ac000

src/nxt_http_compression.c

@@ -305,6 +305,12 @@ nxt_http_comp_compress_static_response(nxt_task_t *task, nxt_http_request_t *r,
 
         cbytes = nxt_http_comp_compress(out + *out_total, out_size - *out_total,
                                         in + in_size - rest, n, last);
+        if (cbytes == -1) {
+            nxt_file_close(task, &tfile);
+            nxt_mem_munmap(in, in_size);
+            nxt_mem_munmap(out, out_size);
+            return NXT_ERROR;
+        }
 
         *out_total += cbytes;
         rest -= n;