diff --git a/src/comstack.c b/src/comstack.c
index ea5b3eef6..6f1f847ef 100644
--- a/src/comstack.c
+++ b/src/comstack.c
@@ -381,6 +381,8 @@ static int cs_complete_http(const char *buf, int len, int head_only)
                     head_only = 1;
                 else if (!memcmp(buf + j, "304", 3))
                     head_only = 1;
+                else
+                    content_len = -1;
                 break;
             }
     }
@@ -406,7 +408,9 @@ static int cs_complete_http(const char *buf, int len, int head_only)
                     return cs_read_chunk(buf, i, len);
                 else
                 {   /* not chunked ; inside body */
-                    if (len >= i + content_len)
+                    if (content_len == -1)
+                        return 0;   /* no content length */
+                    else if (len >= i + content_len)
                     {
                         return i + content_len;
                     }
diff --git a/test/test_comstack.c b/test/test_comstack.c
index 3638d50b7..381ecb88f 100644
--- a/test/test_comstack.c
+++ b/test/test_comstack.c
@@ -170,7 +170,7 @@ static void tst_http_response(void)
 
         YAZ_CHECK_EQ(cs_complete_auto(http_buf, 1), 0);
         YAZ_CHECK_EQ(cs_complete_auto(http_buf, 2), 0);
-        YAZ_CHECK_EQ(cs_complete_auto(http_buf, 24), 19);
+        YAZ_CHECK_EQ(cs_complete_auto(http_buf, 24), 0);
     }
     {
         /* no content, no headers */