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 CBBE93229 for ; Mon, 30 Jan 2023 14:25:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 497ABC433EF; Mon, 30 Jan 2023 14:25:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1675088754; bh=6HrlNku7YbktY9HGS3wwX4E7ykkzUv05r1m+cn1dGag=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zJ38dek8kp4PVGd+cY4z0icDMM3d3iLZH1bL+N/e0du5Ve/ksBZ25xxkS/tFeAk/z SLd+Vc8+Zwvl+HTQlSLPtjTw00xua0KO6qwtBbkHj9oSKjIkFUZYzET955YlL95lJn iINHQxLh9soa1Ady+yirlr9F8d5xPv1s2JvC6bFk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sriram Yagnaraman , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 5.10 125/143] netfilter: conntrack: fix vtag checks for ABORT/SHUTDOWN_COMPLETE Date: Mon, 30 Jan 2023 14:53:02 +0100 Message-Id: <20230130134311.997924005@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230130134306.862721518@linuxfoundation.org> References: <20230130134306.862721518@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Sriram Yagnaraman [ Upstream commit a9993591fa94246b16b444eea55d84c54608282a ] RFC 9260, Sec 8.5.1 states that for ABORT/SHUTDOWN_COMPLETE, the chunk MUST be accepted if the vtag of the packet matches its own tag and the T bit is not set OR if it is set to its peer's vtag and the T bit is set in chunk flags. Otherwise the packet MUST be silently dropped. Update vtag verification for ABORT/SHUTDOWN_COMPLETE based on the above description. Fixes: 9fb9cbb1082d ("[NETFILTER]: Add nf_conntrack subsystem.") Signed-off-by: Sriram Yagnaraman Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nf_conntrack_proto_sctp.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index 7626f3e1c70a..72d0aa603cd6 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -412,22 +412,29 @@ int nf_conntrack_sctp_packet(struct nf_conn *ct, for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { /* Special cases of Verification tag check (Sec 8.5.1) */ if (sch->type == SCTP_CID_INIT) { - /* Sec 8.5.1 (A) */ + /* (A) vtag MUST be zero */ if (sh->vtag != 0) goto out_unlock; } else if (sch->type == SCTP_CID_ABORT) { - /* Sec 8.5.1 (B) */ - if (sh->vtag != ct->proto.sctp.vtag[dir] && - sh->vtag != ct->proto.sctp.vtag[!dir]) + /* (B) vtag MUST match own vtag if T flag is unset OR + * MUST match peer's vtag if T flag is set + */ + if ((!(sch->flags & SCTP_CHUNK_FLAG_T) && + sh->vtag != ct->proto.sctp.vtag[dir]) || + ((sch->flags & SCTP_CHUNK_FLAG_T) && + sh->vtag != ct->proto.sctp.vtag[!dir])) goto out_unlock; } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) { - /* Sec 8.5.1 (C) */ - if (sh->vtag != ct->proto.sctp.vtag[dir] && - sh->vtag != ct->proto.sctp.vtag[!dir] && - sch->flags & SCTP_CHUNK_FLAG_T) + /* (C) vtag MUST match own vtag if T flag is unset OR + * MUST match peer's vtag if T flag is set + */ + if ((!(sch->flags & SCTP_CHUNK_FLAG_T) && + sh->vtag != ct->proto.sctp.vtag[dir]) || + ((sch->flags & SCTP_CHUNK_FLAG_T) && + sh->vtag != ct->proto.sctp.vtag[!dir])) goto out_unlock; } else if (sch->type == SCTP_CID_COOKIE_ECHO) { - /* Sec 8.5.1 (D) */ + /* (D) vtag must be same as init_vtag as found in INIT_ACK */ if (sh->vtag != ct->proto.sctp.vtag[dir]) goto out_unlock; } else if (sch->type == SCTP_CID_HEARTBEAT) { -- 2.39.0