From: Jeremy Harris <jgh146exb@wizmail.org>
Date: Sat, 27 Apr 2019 12:22:52 +0000 (+0100)
Subject: ARC: harden against malformed headers
X-Git-Tag: exim-4.93-RC0~216
X-Git-Url: https://git.exim.org/exim.git/commitdiff_plain/b4dd15a736795e6d06a79febbae76a926964bbb0

ARC: harden against malformed headers
---

diff --git a/src/src/arc.c b/src/src/arc.c
index 6c4bcc641..e7ebb9719 100644
--- a/src/src/arc.c
+++ b/src/src/arc.c
@@ -260,6 +260,7 @@ while ((c = *s))
 	  while ((c = *++s) && c != ';')
 	    if (c != ' ' && c != '\t' && c != '\n' && c != '\r')
 	      g = string_catn(g, s, 1);
+	  if (!g) return US"no b= value";
 	  al->b.data = string_from_gstring(g);
 	  al->b.len = g->ptr;
 	  gstring_reset_unused(g);
@@ -276,6 +277,7 @@ while ((c = *s))
 	  while ((c = *++s) && c != ';')
 	    if (c != ' ' && c != '\t' && c != '\n' && c != '\r')
 	      g = string_catn(g, s, 1);
+	  if (!g) return US"no bh= value";
 	  al->bh.data = string_from_gstring(g);
 	  al->bh.len = g->ptr;
 	  gstring_reset_unused(g);