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 CA87B54BD4; Tue, 27 Feb 2024 13:49:01 +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=1709041741; cv=none; b=Q6eUF4eiAs/SdvYXt3hXTGNhF3+A6S63ZD7DREgTchEV51Smr9iK5by/LKV/+NCPh5YX/QoWuMocnTMpkbJSJdgcTYX3Ol1b0c/xMq2xvdJdPZG13oD7PyK/sKuKcxlFosT0LtBgT08ZdX0snTl0tp61zaaGbGKtbJ4DDthiXIU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709041741; c=relaxed/simple; bh=Tuujnbyk+BqesRBp/TnPf5BRspcBZEm93DT56W1jGy0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SbQUuLsFO2VUmyf5VrOzE5g4OLy0w20cffrjDX2GVpK149eaDrU1RRTaChklSb5UAdYwTqxWW3ThUXVvvXoSQ7sQWRSFweGBk9VOFdWAKQENtqxFGojNscA0YBKvo+ZFbMddwwtLHdsgXzaKC6Ip8Je8T2TOOwQg2w7j/e2+kNw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=a/RMOXJf; 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="a/RMOXJf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 589F1C433C7; Tue, 27 Feb 2024 13:49:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1709041741; bh=Tuujnbyk+BqesRBp/TnPf5BRspcBZEm93DT56W1jGy0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a/RMOXJfISWTmG550xf3ngvFFwXjT53MtdBBhy+Nj47091Xp4IOxzO/+K8Qe6ZI88 ms7nUZi4+M26FIo/GrwNsZNYrUccipsGSaPRqmd2v98PqODN1h7tGyoQJtF09waH97 E9jNtNrAHveHQaJwKvss5fURa+LWMtkGyE+t9PQE= 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 6.6 052/299] netfilter: conntrack: check SCTP_CID_SHUTDOWN_ACK for vtag setting in sctp_new Date: Tue, 27 Feb 2024 14:22:43 +0100 Message-ID: <20240227131627.645587335@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240227131625.847743063@linuxfoundation.org> References: <20240227131625.847743063@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 6.6-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 c6bd533983c1f..4cc97f971264e 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -283,7 +283,7 @@ 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