From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: passt.top; dkim=pass (2048-bit key; secure) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.a=rsa-sha256 header.s=202510 header.b=IdOKEj8t; dkim-atps=neutral Received: from mail.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by passt.top (Postfix) with ESMTPS id 656355A0622 for ; Sat, 11 Oct 2025 06:49:33 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202510; t=1760158165; bh=33dVEI4qhQV/3lO9EICIgwq8xDmETHGcBpiBrQL5HfQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IdOKEj8tEFGzBsR/OSfIYOZS0qFcVFm7EJ0XloGRFOft654VYcJNjD81jNyeT9h2a p6rEAHmjpyWvRb8Z1JRr1BTcDUCvrbXBkYpH9VMr34C0k+3XHbh5RHfQPXt0Nf1Ewm uIgaBDng4sKBtr8zp5bhKGh4q7n+tiW28bYKiq6eJtExi176MSeu4J1bpMHIJgzh0R WuqY88nL9IPIx/GFdpALDcl6yyMnLCrMbS1KbrbRd0BOMwhV/EriBYMXtOUHmiCCOE 0iJR/BFyI9mvBqIxgErvM00wY+Muhi1nAMGJ79jR4HTOHob+npDJ8uZnBbYgLDB1PD OB+0/ZKWPmAvQ== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4ckB3T5mYyz4wDC; Sat, 11 Oct 2025 15:49:25 +1100 (AEDT) From: David Gibson To: passt-dev@passt.top, Stefano Brivio Subject: [PATCH 8/8] tcp, udp: Don't exclude ports in {tcp,udp}_port_rebind() Date: Sat, 11 Oct 2025 15:48:27 +1100 Message-ID: <20251011044827.862757-9-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251011044827.862757-1-david@gibson.dropbear.id.au> References: <20251011044827.862757-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: 5MARMG4URO5XP4TUWTMG2552QSEPP5KI X-Message-ID-Hash: 5MARMG4URO5XP4TUWTMG2552QSEPP5KI X-MailFrom: dgibson@gandalf.ozlabs.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: David Gibson X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: To avoid circular forwarding, {tcp,udp}_port_rebind() refuse to listen on ports that we're already listening on in the reverse direction. This is redundant, because we already remove such ports from the forward map when we scan. I believe this was needed, because previously our reverse maps might be one cycle out of date, so could be missing a newly appeared port. We've now rearrange the port scanning code to avoid that, so we don't need the check in tcp_port_rebind() any more. Signed-off-by: David Gibson --- tcp.c | 5 ----- udp.c | 6 ------ 2 files changed, 11 deletions(-) diff --git a/tcp.c b/tcp.c index a330538d..99a8a4c0 100644 --- a/tcp.c +++ b/tcp.c @@ -2817,7 +2817,6 @@ int tcp_init(struct ctx *c) static void tcp_port_rebind(struct ctx *c, bool outbound) { const uint8_t *fmap = outbound ? c->tcp.fwd_out.map : c->tcp.fwd_in.map; - const uint8_t *rmap = outbound ? c->tcp.fwd_in.map : c->tcp.fwd_out.map; int (*socks)[IP_VERSIONS] = outbound ? tcp_sock_ns : tcp_sock_init_ext; unsigned port; @@ -2836,10 +2835,6 @@ static void tcp_port_rebind(struct ctx *c, bool outbound) continue; } - /* Don't loop back our own ports */ - if (bitmap_isset(rmap, port)) - continue; - if ((c->ifi4 && socks[port][V4] == -1) || (c->ifi6 && socks[port][V6] == -1)) { if (outbound) diff --git a/udp.c b/udp.c index e27b2219..4af98503 100644 --- a/udp.c +++ b/udp.c @@ -1191,8 +1191,6 @@ static void udp_port_rebind(struct ctx *c, bool outbound) int (*socks)[NUM_PORTS] = outbound ? udp_splice_ns : udp_splice_init; const uint8_t *fmap = outbound ? c->udp.fwd_out.map : c->udp.fwd_in.map; - const uint8_t *rmap - = outbound ? c->udp.fwd_in.map : c->udp.fwd_out.map; unsigned port; for (port = 0; port < NUM_PORTS; port++) { @@ -1210,10 +1208,6 @@ static void udp_port_rebind(struct ctx *c, bool outbound) continue; } - /* Don't loop back our own ports */ - if (bitmap_isset(rmap, port)) - continue; - if ((c->ifi4 && socks[V4][port] == -1) || (c->ifi6 && socks[V6][port] == -1)) udp_sock_init(c, outbound, NULL, NULL, port); -- 2.51.0