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 2481113848B; Wed, 7 Feb 2024 21:22:28 +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=1707340948; cv=none; b=TNp284TpDh/8hr0y4Ddr61NvWCi4cgjo94Ca/daGV2oUIjHh476I1tNzu6PfuBPr2SfLMLu8p3fXh4ipwOEMZMnAaDi7R8KzMejC7PEpEwq1eCuUc3a86+Ra/JN5OS2KwNvhj1j0CMrNrf8OOx6qLH5SdUXSSj1kO272JLS6+1o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707340948; c=relaxed/simple; bh=mX/ebMEh7thQzNklaYbubtROwsv/Ojpwrtwuq4H+bIQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=clBd80sUnOLoy42YzwjS6WQPfjs5NqEWMfTznxQ3syvDP+sIdgx++HKBpLXkk1ymd+wpaUBH3K7YHVri/rpDcx3G8+5a2nTKwFG8I5rPYI5Rd0kGLlSqRY8cnhO0nwEctc5rr4F7IpCITqIcaw5k2RX+P/jx3uP9QCsneeoG5Kg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gAxG6UY1; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gAxG6UY1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4D711C43390; Wed, 7 Feb 2024 21:22:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1707340948; bh=mX/ebMEh7thQzNklaYbubtROwsv/Ojpwrtwuq4H+bIQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gAxG6UY1eerxfeWVe6m946afcIsUmASbcXw6bQxjxTYScQmwM0p7pot7tN4XD77MB QJfPZSI0oV3uDnVrEERufpdPfOE/jKrHkJSILMxGXgcnr/hKGmTWZ7nRWOK7v1SNJM 50CgszxQL/9P93AnDffxUZY8lE5e0Imj28VaV9iHptyepkTkQ/vnz9I7KiA1Tc9S2O 5dY/vj2J6rUGYHDyBftb1/bEwU7vByt9M9C2+DHnNTF3AmF64jlEolNfj3rI6gqYXn oUPatY7BfPRnwaIt6lFbni+fXBzC9ZS506tcKaYluvy/bKftU4A0poNsR/d1IZoI8v KTDp6fEUmOM8A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Xin Long , Pablo Neira Ayuso , Sasha Levin , kadlec@netfilter.org, fw@strlen.de, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 6.7 23/44] netfilter: conntrack: check SCTP_CID_SHUTDOWN_ACK for vtag setting in sctp_new Date: Wed, 7 Feb 2024 16:20:50 -0500 Message-ID: <20240207212142.1399-23-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240207212142.1399-1-sashal@kernel.org> References: <20240207212142.1399-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.7.4 Content-Transfer-Encoding: 8bit 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 c6bd533983c1..4cc97f971264 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