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 5EFCA2AF15; Tue, 10 Sep 2024 10:41:29 +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=1725964889; cv=none; b=KotRKsvKnjeAup+2R1bYPSuf3XvWZ4tp8UzyrwVbMhY0c3gn1vKcUAFvaXsQo/TQswTaD5+Y2R7wKOMvmC1euPyAyj4gEI2mq+x4G2hfvqWcrMt7e3noVyrn++mxXuGq+djbsfW7Hmq3TikejyxN+pNVosGcaUGjmrAkuoJQF7o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725964889; c=relaxed/simple; bh=eFnGCDAFaDj8H2r2W7Jaq7uRrLzEKAhmyD6wU+SwsKw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JqkeAbKJ0QqUkuFhtAzxwP92J2FoMyMaHdrf2L/lX8/+lOrAu6LYsFyKVFWEB2rxy2YOwyerMTiLn3VdJLA6mqC7MSoGR0u/G87O2Avb/ikwjmHrG3x6m9aU4yfJYXizbhcESSUoAcB9cb5yhvQQkIIz2eNbUja929mV4nGlpy8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=T26MIJIJ; 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="T26MIJIJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DBE50C4CEC3; Tue, 10 Sep 2024 10:41:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1725964889; bh=eFnGCDAFaDj8H2r2W7Jaq7uRrLzEKAhmyD6wU+SwsKw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=T26MIJIJnPxV9VNycfEgM76iL0nVsEr0PSPFEhm6Y10FLv4age33HSKUZHdUVSr1X Wjq3z6Q2L7kyQFdHHMPX8eDtEYV3IPcXBdoeswfHLNlBi3MwvOuboLbqU16lEN4Ku9 yGtOrB2SoaFvPoljV89wmuddwvhiIDPcDFxgziuA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Konstantin Andreev , Casey Schaufler , Sasha Levin Subject: [PATCH 5.10 038/186] smack: tcp: ipv4, fix incorrect labeling Date: Tue, 10 Sep 2024 11:32:13 +0200 Message-ID: <20240910092556.112509909@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240910092554.645718780@linuxfoundation.org> References: <20240910092554.645718780@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Casey Schaufler [ Upstream commit 2fe209d0ad2e2729f7e22b9b31a86cc3ff0db550 ] Currently, Smack mirrors the label of incoming tcp/ipv4 connections: when a label 'foo' connects to a label 'bar' with tcp/ipv4, 'foo' always gets 'foo' in returned ipv4 packets. So, 1) returned packets are incorrectly labeled ('foo' instead of 'bar') 2) 'bar' can write to 'foo' without being authorized to write. Here is a scenario how to see this: * Take two machines, let's call them C and S, with active Smack in the default state (no settings, no rules, no labeled hosts, only builtin labels) * At S, add Smack rule 'foo bar w' (labels 'foo' and 'bar' are instantiated at S at this moment) * At S, at label 'bar', launch a program that listens for incoming tcp/ipv4 connections * From C, at label 'foo', connect to the listener at S. (label 'foo' is instantiated at C at this moment) Connection succeedes and works. * Send some data in both directions. * Collect network traffic of this connection. All packets in both directions are labeled with the CIPSO of the label 'foo'. Hence, label 'bar' writes to 'foo' without being authorized, and even without ever being known at C. If anybody cares: exactly the same happens with DCCP. This behavior 1st manifested in release 2.6.29.4 (see Fixes below) and it looks unintentional. At least, no explanation was provided. I changed returned packes label into the 'bar', to bring it into line with the Smack documentation claims. Signed-off-by: Konstantin Andreev Signed-off-by: Casey Schaufler Signed-off-by: Sasha Levin --- security/smack/smack_lsm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 8c790563b33a..88bcda1f07bf 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -4228,7 +4228,7 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, rcu_read_unlock(); if (hskp == NULL) - rc = netlbl_req_setattr(req, &skp->smk_netlabel); + rc = netlbl_req_setattr(req, &ssp->smk_out->smk_netlabel); else netlbl_req_delattr(req); -- 2.43.0