[3.0] c9db023 Return false if req.backend.health is accessed in vcl_deliver{} where this information is no longer available.

[Tollef Fog Heen]

commit c9db023f8c83f9f11199e09073ccfd8ecd320181
Author: Poul-Henning Kamp <phk at FreeBSD.org>
Date:   Tue Apr 9 13:05:14 2013 +0200

    Return false if req.backend.health is accessed in vcl_deliver{} where
    this information is no longer available.
    
    Fixes #1228

diff --git a/bin/varnishd/cache_vrt_var.c b/bin/varnishd/cache_vrt_var.c
index 9a2e500..189d8e9 100644
--- a/bin/varnishd/cache_vrt_var.c
+++ b/bin/varnishd/cache_vrt_var.c
@@ -536,6 +536,12 @@ unsigned
 VRT_r_req_backend_healthy(const struct sess *sp)
 {
 	CHECK_OBJ_NOTNULL(sp, SESS_MAGIC);
+       /*
+        * XXX: Not optimal, but we do not have a backend in vcl_deliver
+        * XXX: and we have to return something.
+        */
+       if (sp->director == NULL)
+	       return (0);
 	CHECK_OBJ_NOTNULL(sp->director, DIRECTOR_MAGIC);
 	return (VDI_Healthy(sp->director, sp));
 }
diff --git a/bin/varnishtest/tests/r01228.vcl b/bin/varnishtest/tests/r01228.vcl
new file mode 100644
index 0000000..33bf365
--- /dev/null
+++ b/bin/varnishtest/tests/r01228.vcl
@@ -0,0 +1,18 @@
+varnishtest "req.backend.healthy in vcl_deliver"
+
+server s1 {
+       rxreq
+       txresp
+} -start
+
+varnish v1 -vcl+backend {
+       sub vcl_deliver {
+           set resp.http.x-foo = req.backend.healthy;
+       }
+} -start
+
+client c1 {
+       txreq
+       rxresp
+       expect resp.status == 200
+} -run