From: Thierry FOURNIER <thierry.fournier@ozon.io>
Date: Fri, 25 May 2018 14:27:44 +0000 (+0200)
Subject: BUG/MEDIUM: lua/socket: Length required read doesn't work
X-Git-Tag: v1.9-dev1~245
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8c126c7235ced98986a57175a62503d5166ffe19;p=thirdparty%2Fhaproxy.git

BUG/MEDIUM: lua/socket: Length required read doesn't work

The limit of data read works only if all the data is in the
input buffer. Otherwise (if the data arrive in chunks), the
total amount of data is not taken in acount.

Only the current read data are compared to the expected amout
of data.

This patch must be backported from 1.9 to 1.6
---

diff --git a/src/hlua.c b/src/hlua.c
index 727d664843..78d9cade72 100644
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -1676,6 +1676,7 @@ __LJMP static int hlua_socket_receive_yield(struct lua_State *L, int status, lua
 	struct stream_interface *si;
 	struct stream *s;
 	struct xref *peer;
+	int missing_bytes;
 
 	/* Check if this lua stack is schedulable. */
 	if (!hlua || !hlua->task)
@@ -1745,11 +1746,12 @@ __LJMP static int hlua_socket_receive_yield(struct lua_State *L, int status, lua
 		if (nblk == 0) /* No data avalaible. */
 			goto connection_empty;
 
-		if (len1 > wanted) {
+		missing_bytes = wanted - socket->b.n;
+		if (len1 > missing_bytes) {
 			nblk = 1;
-			len1 = wanted;
-		} if (nblk == 2 && len1 + len2 > wanted)
-			len2 = wanted - len1;
+			len1 = missing_bytes;
+		} if (nblk == 2 && len1 + len2 > missing_bytes)
+			len2 = missing_bytes - len1;
 	}
 
 	len = len1;
@@ -1772,7 +1774,7 @@ __LJMP static int hlua_socket_receive_yield(struct lua_State *L, int status, lua
 	 */
 	if (wanted == HLSR_READ_ALL)
 		goto connection_empty;
-	else if (wanted >= 0 && len < wanted)
+	else if (wanted >= 0 && socket->b.n < wanted)
 		goto connection_empty;
 
 	/* Return result. */