From 73befed1a6950f5312e3a422dde82a7bb5a8bbe3 Mon Sep 17 00:00:00 2001
From: Martin Blix Grydeland <martin@varnish-software.com>
Date: Thu, 15 Aug 2019 11:16:22 +0200
Subject: [PATCH] Do not set the proto txt.b value when third field is missing

In http1_splitline, if the third field is missing, we would still set the
txt.b value to where the field would have been, with a NULL txt.e
entry. This would cause http_Proto to attempt to parse the values
there. Fix this by only setting the .b and .e if the third field was
present.
---
 bin/varnishd/http1/cache_http1_proto.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/bin/varnishd/http1/cache_http1_proto.c b/bin/varnishd/http1/cache_http1_proto.c
index af9ca3898c..e55555bf19 100644
--- a/bin/varnishd/http1/cache_http1_proto.c
+++ b/bin/varnishd/http1/cache_http1_proto.c
@@ -272,7 +272,6 @@ http1_splitline(struct http *hp, struct http_conn *htc, const int *hf,
 		if (vct_isctl(*p))
 			return (400);
 	}
-	hp->hd[hf[2]].b = p;
 	if (q < p)
 		*q = '\0';	/* Nul guard for the 2nd field. If q == p
 				 * (the third optional field is not
@@ -280,13 +279,15 @@ http1_splitline(struct http *hp, struct http_conn *htc, const int *hf,
 				 * cover this field. */
 
 	/* Third field is optional and cannot contain CTL except TAB */
+	q = p;
 	for (; p < htc->rxbuf_e && !vct_iscrlf(p, htc->rxbuf_e); p++) {
-		if (vct_isctl(*p) && !vct_issp(*p)) {
-			hp->hd[hf[2]].b = NULL;
+		if (vct_isctl(*p) && !vct_issp(*p))
 			return (400);
-		}
 	}
-	hp->hd[hf[2]].e = p;
+	if (p > q) {
+		hp->hd[hf[2]].b = q;
+		hp->hd[hf[2]].e = p;
+	}
 
 	/* Skip CRLF */
 	i = vct_iscrlf(p, htc->rxbuf_e);
