From: Christopher Faulet <cfaulet@haproxy.com>
Date: Wed, 3 Mar 2021 18:36:51 +0000 (+0100)
Subject: BUG/MINOR: hlua: Don't strip last non-LWS char in hlua_pushstrippedstring()
X-Git-Tag: v2.4-dev11~39
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2ec4e3c1acf95bcdc56028bbefe1a355c457b978;p=thirdparty%2Fhaproxy.git

BUG/MINOR: hlua: Don't strip last non-LWS char in hlua_pushstrippedstring()

hlua_pushstrippedstring() function strips leading and trailing LWS
characters. But the result length it too short by 1 byte. Thus the last
non-LWS character is stripped. Note that a string containing only LWS
characters resulting to a stipped string with an invalid length (-1). This
leads to a lua runtime error.

This bug was reported in the issue #1155. It must be backported as far as
1.7.
---

diff --git a/src/hlua_fcn.c b/src/hlua_fcn.c
index c2d26817ac..46a807e58f 100644
--- a/src/hlua_fcn.c
+++ b/src/hlua_fcn.c
@@ -172,12 +172,13 @@ int hlua_fcn_pushfield(lua_State *L, struct field *field)
 const char *hlua_pushstrippedstring(lua_State *L, const char *str)
 {
 	const char *p;
-	const char *e;
+	int l;
 
 	for (p = str; HTTP_IS_LWS(*p); p++);
-	for (e = p + strlen(p) - 1; e > p && HTTP_IS_LWS(*e); e--);
 
-	return lua_pushlstring(L, p, e - p);
+	for (l = strlen(p); l && HTTP_IS_LWS(p[l-1]); l--);
+
+	return lua_pushlstring(L, p, l);
 }
 
 /* The three following functions are useful for adding entries