From 70d318ccb760ee25f166a75d163f38545f074ff1 Mon Sep 17 00:00:00 2001 From: Thierry FOURNIER Date: Sat, 30 Jun 2018 10:37:33 +0200 Subject: [PATCH] BUG/MEDIUM: lua: possible CLOSE-WAIT state with '\n' headers The Lua parser doesn't takes in account end-of-headers containing only '\n'. It expects always '\r\n'. If a '\n' is processes the Lua parser considers it miss 1 byte, and wait indefinitely for new data. When the client reaches their timeout, it closes the connection. This close is not detected and the connection keep in CLOSE-WAIT state. I guess that this patch fix only a visible part of the problem. If the Lua HTTP parser wait for data, the timeout server or the connectio closed by the client may stop the applet. How reproduce the problem: HAProxy conf: global lua-load bug38.lua frontend frt timeout client 2s timeout server 2s mode http bind *:8080 http-request use-service lua.donothing Lua conf core.register_service("donothing", "http", function(applet) end) Client request: echo -ne 'GET / HTTP/1.1\n\n' | nc 127.0.0.1 8080 Look for CLOSE-WAIT in the connection with "netstat" or "ss". I use this script: while sleep 1; do ss | grep CLOSE-WAIT; done This patch must be backported in 1.6, 1.7 and 1.8 Workaround: enable the "hard-stop-after" directive, and perform periodic reload. --- src/hlua.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/hlua.c b/src/hlua.c index 93ec44c3b7..4715639a16 100644 --- a/src/hlua.c +++ b/src/hlua.c @@ -6663,13 +6663,13 @@ static void hlua_applet_http_fct(struct appctx *ctx) len2 = 0; if (ret == 0) len1 = 0; - if (len1 + len2 < strm->txn->req.eoh + 2) { + if (len1 + len2 < strm->txn->req.eoh + strm->txn->req.eol) { si_applet_cant_get(si); return; } /* skip the requests bytes. */ - co_skip(si_oc(si), strm->txn->req.eoh + 2); + co_skip(si_oc(si), strm->txn->req.eoh + strm->txn->req.eol); } /* Executes The applet if it is not done. */ -- 2.39.5