Fix a cornercase of chunked encoding and malloc stevedore:

Don't try to trim a storage segment we filled completely.

Fixes: #776



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@5217 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache_fetch.c

@@ -210,7 +210,7 @@ fetch_chunked(struct sess *sp, struct http_conn *htc)
 	if (st != NULL && st->len == 0) {
 		VTAILQ_REMOVE(&sp->obj->store, st, list);
 		STV_free(st);
-	} else if (st != NULL)
+	} else if (st != NULL && st->len < st->space)
 		STV_trim(st, st->len);
 	return (0);
 }
@@ -275,7 +275,7 @@ fetch_eof(struct sess *sp, struct http_conn *htc)
 	if (st->len == 0) {
 		VTAILQ_REMOVE(&sp->obj->store, st, list);
 		STV_free(st);
-	} else
+	} else 
 		STV_trim(st, st->len);
 
 	return (1);

bin/varnishtest/tests/r00776.vtc

+# $Id$
+
+test "Edge case of chunked encoding, trimming storage to length."
+
+server s1 {
+	rxreq
+	txresp -nolen -hdr "Transfer-encoding: chunked"
+	chunkedlen 4096
+} -start
+
+varnish v1 \
+	-arg "-p fetch_chunksize=4" \
+	-arg "-s malloc,1m" -vcl+backend { } -start
+
+client c1 {
+	txreq 
+	rxresp
+} -run