From patchwork Tue Oct 1 14:12:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Micka=C3=ABl_Sala=C3=BCn?= X-Patchwork-Id: 13818158 Received: from smtp-190d.mail.infomaniak.ch (smtp-190d.mail.infomaniak.ch [185.125.25.13]) (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 F3EA41C1733 for ; Tue, 1 Oct 2024 14:29:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.125.25.13 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727792976; cv=none; b=nX9WA0pU9BnDcyR/xutxOE1wn4yQ6JO5ZYcFKGyiE/UF4Meuw9fn1htoiPb3OfxiZQzE/+GFHXG7cD2aP2n30OWhw+OlAUi83Tbpxj9xMHcMAKSZz2MA4Hg18uRJi8OnhnrTjtpAXAWChGWInmHdypmpDQ/hecRToeFmUkGY6iw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727792976; c=relaxed/simple; bh=ueKXlRKbUxKgW/VYitwtQFQ3oZkGIkwxW/mJgtz7r7g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=LHjh1DUoDNSLFvpPNzsQMy3LJXsDZyzG5hfKrpQru08J/0EOxAq2W9honw7Di9L5tRRgctJxHeSYwIy+JBceJrDorpIOqnNUACaMAVP9eJL6G19Vzp85LP7XHd6xi46rRnA3m7Rd9xabI51bsNeyZ118UOtZ0kfryMkV1wpXxVQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=digikod.net; spf=pass smtp.mailfrom=digikod.net; dkim=pass (1024-bit key) header.d=digikod.net header.i=@digikod.net header.b=QJi0lLhu; arc=none smtp.client-ip=185.125.25.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=digikod.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=digikod.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=digikod.net header.i=@digikod.net header.b="QJi0lLhu" Received: from smtp-4-0000.mail.infomaniak.ch (smtp-4-0000.mail.infomaniak.ch [10.7.10.107]) by smtp-4-3000.mail.infomaniak.ch (Postfix) with ESMTPS id 4XJ0JZ0dnZz4fm; Tue, 1 Oct 2024 16:12:46 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=digikod.net; s=20191114; t=1727791965; bh=Dj0MGq2F7eT7dWux7TQJIkSeSK0bidTDsqd/S578HcA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QJi0lLhu4AnjRR2h9kdlOuBQ6LsMCmMm+0cDxL8LofGgcPPVvrppWmdhskTd6WASl 7oygurNxglPypTxibL5oxxydqsRCd9bgfaK+KdXUKs2yPVEfYDEzEWaCP4X47k0Kdr E7HAIh/kTwCA+/mc1wINsc4UxfGavJOsz1TQaLGw= Received: from unknown by smtp-4-0000.mail.infomaniak.ch (Postfix) with ESMTPA id 4XJ0JY2RsbzYqn; Tue, 1 Oct 2024 16:12:45 +0200 (CEST) From: =?utf-8?q?Micka=C3=ABl_Sala=C3=BCn?= To: =?utf-8?q?G=C3=BCnther_Noack?= , Mikhail Ivanov Cc: =?utf-8?q?Micka=C3=ABl_Sala=C3=BCn?= , Konstantin Meskhidze , Paul Moore , Tahera Fahimi , linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org Subject: [PATCH v1 3/3] landlock: Optimize scope enforcement Date: Tue, 1 Oct 2024 16:12:34 +0200 Message-ID: <20241001141234.397649-4-mic@digikod.net> In-Reply-To: <20241001141234.397649-1-mic@digikod.net> References: <20241001141234.397649-1-mic@digikod.net> Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Infomaniak-Routing: alpha Do not walk through the domain hierarchy when the required scope is not supported by this domain. This is the same approach as for filesystem and network restrictions. Cc: Günther Noack Cc: Mikhail Ivanov Cc: Tahera Fahimi Signed-off-by: Mickaël Salaün Link: https://lore.kernel.org/r/20241001141234.397649-4-mic@digikod.net --- security/landlock/task.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) diff --git a/security/landlock/task.c b/security/landlock/task.c index 4acbd7c40eee..02e3a0330b21 100644 --- a/security/landlock/task.c +++ b/security/landlock/task.c @@ -204,12 +204,22 @@ static bool is_abstract_socket(struct sock *const sock) return false; } +static const struct landlock_ruleset *get_current_unix_scope_domain(void) +{ + const union access_masks unix_scope = { + .scope = LANDLOCK_SCOPE_ABSTRACT_UNIX_SOCKET, + }; + + return landlock_filter_access_masks(landlock_get_current_domain(), + unix_scope); +} + static int hook_unix_stream_connect(struct sock *const sock, struct sock *const other, struct sock *const newsk) { const struct landlock_ruleset *const dom = - landlock_get_current_domain(); + get_current_unix_scope_domain(); /* Quick return for non-landlocked tasks. */ if (!dom) @@ -225,7 +235,7 @@ static int hook_unix_may_send(struct socket *const sock, struct socket *const other) { const struct landlock_ruleset *const dom = - landlock_get_current_domain(); + get_current_unix_scope_domain(); if (!dom) return 0; @@ -243,6 +253,10 @@ static int hook_unix_may_send(struct socket *const sock, return 0; } +static const union access_masks signal_scope = { + .scope = LANDLOCK_SCOPE_SIGNAL, +}; + static int hook_task_kill(struct task_struct *const p, struct kernel_siginfo *const info, const int sig, const struct cred *const cred) @@ -256,6 +270,7 @@ static int hook_task_kill(struct task_struct *const p, } else { dom = landlock_get_current_domain(); } + dom = landlock_filter_access_masks(dom, signal_scope); /* Quick return for non-landlocked tasks. */ if (!dom) @@ -279,7 +294,8 @@ static int hook_file_send_sigiotask(struct task_struct *tsk, /* Lock already held by send_sigio() and send_sigurg(). */ lockdep_assert_held(&fown->lock); - dom = landlock_file(fown->file)->fown_domain; + dom = landlock_filter_access_masks( + landlock_file(fown->file)->fown_domain, signal_scope); /* Quick return for unowned socket. */ if (!dom)