From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8EA7678B61; Tue, 27 Feb 2024 14:02:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709042564; cv=none; b=cI0q5Lkz4oBTJthd6aKraw8i4tJgdJq5f2/2TRXCfPbjEDLtjnm2xxWjhpo/w+VvY7w39jXpzluc3HRLwnEcGzeAN2K+1K2lKQZDL2HDroFy7nNkS1zjyypPloIMZsXQabgGC+ALDsayiA8Qlls76F5n7OnITEcvzFd+1YM1EUk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709042564; c=relaxed/simple; bh=vgquAS39ogx4KyR+xztAcrIbcty83WtkqxPfvMVY8cM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cKHIDV8miME/0zqLgeVGRjJqmV07/v3ee7oP/JCxZ1/b9XDoI8vy2YX8JOq+2bSVsnQ7bXxeSGHDyMkOJv2O3Y9vBJi4YZIOsSrKrZvrPOjz8gPiLMV+Z6VTt4msTyyuxNo5xhuqAlCJ9U6vmI9RqLlx8AC1EmwKgYJ9Qh8qzRA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=c2QMhkZz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="c2QMhkZz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0FEBDC433C7; Tue, 27 Feb 2024 14:02:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1709042564; bh=vgquAS39ogx4KyR+xztAcrIbcty83WtkqxPfvMVY8cM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c2QMhkZzXiL/jd6OZaMS9NqUu4KmooEyUGJEYyoHdaaUxHuBjA3P6yYHyGCd7LML+ cyG6tzxxHjAMHLtyCgVfaUCs0PYxPocR8oRKXrCgiAZT+ApGjKwNbxWksYnSF9C1C7 +fIL64USb3PSOz1LOWwUsH18kphzo4dILwktl400= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xin Long , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 5.15 040/245] netfilter: conntrack: check SCTP_CID_SHUTDOWN_ACK for vtag setting in sctp_new Date: Tue, 27 Feb 2024 14:23:48 +0100 Message-ID: <20240227131616.423704855@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240227131615.098467438@linuxfoundation.org> References: <20240227131615.098467438@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long [ Upstream commit 6e348067ee4bc5905e35faa3a8fafa91c9124bc7 ] The annotation says in sctp_new(): "If it is a shutdown ack OOTB packet, we expect a return shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8)". However, it does not check SCTP_CID_SHUTDOWN_ACK before setting vtag[REPLY] in the conntrack entry(ct). Because of that, if the ct in Router disappears for some reason in [1] with the packet sequence like below: Client > Server: sctp (1) [INIT] [init tag: 3201533963] Server > Client: sctp (1) [INIT ACK] [init tag: 972498433] Client > Server: sctp (1) [COOKIE ECHO] Server > Client: sctp (1) [COOKIE ACK] Client > Server: sctp (1) [DATA] (B)(E) [TSN: 3075057809] Server > Client: sctp (1) [SACK] [cum ack 3075057809] Server > Client: sctp (1) [HB REQ] (the ct in Router disappears somehow) <-------- [1] Client > Server: sctp (1) [HB ACK] Client > Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810] Client > Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810] Client > Server: sctp (1) [HB REQ] Client > Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810] Client > Server: sctp (1) [HB REQ] Client > Server: sctp (1) [ABORT] when processing HB ACK packet in Router it calls sctp_new() to initialize the new ct with vtag[REPLY] set to HB_ACK packet's vtag. Later when sending DATA from Client, all the SACKs from Server will get dropped in Router, as the SACK packet's vtag does not match vtag[REPLY] in the ct. The worst thing is the vtag in this ct will never get fixed by the upcoming packets from Server. This patch fixes it by checking SCTP_CID_SHUTDOWN_ACK before setting vtag[REPLY] in the ct in sctp_new() as the annotation says. With this fix, it will leave vtag[REPLY] in ct to 0 in the case above, and the next HB REQ/ACK from Server is able to fix the vtag as its value is 0 in nf_conntrack_sctp_packet(). Signed-off-by: Xin Long Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nf_conntrack_proto_sctp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index c94a9971d790c..7ffd698497f2a 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -299,7 +299,7 @@ sctp_new(struct nf_conn *ct, const struct sk_buff *skb, pr_debug("Setting vtag %x for secondary conntrack\n", sh->vtag); ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = sh->vtag; - } else { + } else if (sch->type == SCTP_CID_SHUTDOWN_ACK) { /* If it is a shutdown ack OOTB packet, we expect a return shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8) */ pr_debug("Setting vtag %x for new conn OOTB\n", -- 2.43.0