From patchwork Sat Nov 9 11:08:56 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: 13869422 Received: from smtp-42ad.mail.infomaniak.ch (smtp-42ad.mail.infomaniak.ch [84.16.66.173]) (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 1B896154C12 for ; Sat, 9 Nov 2024 11:25:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=84.16.66.173 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731151516; cv=none; b=lhuWV77aJ54QgdWew/Lmw+cN7cVn/JGvcSR7k4T1npFzX4tTIj/NQXI21NguuDcZEswOGkULci01lhUXAIaqWiBD5FuVQqSjT5sBbQ+ZEjPyP4D5UaSHgeum0Uc/UyhA5wJZMYTUkN4WHzN2suPD6XbmE+SkBqRQO/pFtIEiIMo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731151516; c=relaxed/simple; bh=Ia5hTMOLKaax1IxZmH3a+EoHfBXcP6f9RKCxsxQBfmE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=cVEwUbeBw5ccuCt57jM7rzNPxfJ6C10g2yRqDPo6xDV+Y8P7lU+DvmZk9YEOJJ7KnP8UT20wnbHsbC42WwcZbOvWbdpNPW7NmMbzFwR2cnJzPbCS5lrTTYkQrVlpYIUs1YvSvYd/LvcfTjPzSmZ3Wd6PTysiRBI4VDZsiTtVzAE= 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=JC/H7GsM; arc=none smtp.client-ip=84.16.66.173 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="JC/H7GsM" Received: from smtp-4-0001.mail.infomaniak.ch (smtp-4-0001.mail.infomaniak.ch [10.7.10.108]) by smtp-4-3000.mail.infomaniak.ch (Postfix) with ESMTPS id 4XltNj07LFz7xw; Sat, 9 Nov 2024 12:09:09 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=digikod.net; s=20191114; t=1731150548; bh=UvZP4U1+PJ/HP+QehB8ZwzNPYbHZqDuMCkn9yYHrC3g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JC/H7GsMStKSqzeD1NZosXeyyUeQOuqhko9No2y8QPs0y7ipm/a2oxl3KMS9JrwBz UIlFrTXzhTCH3eHsiNL4T+EDA+mUDvUjK/pOsrsL3ulg5CYAae6+s2eL8IaAOG35/h 0mHD1IQ8PqfeTgS5Q0QxHqiON1/KrnFQ2eHdNVGM= Received: from unknown by smtp-4-0001.mail.infomaniak.ch (Postfix) with ESMTPA id 4XltNh1qDFzs4C; Sat, 9 Nov 2024 12:09:08 +0100 (CET) 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 v4 3/3] landlock: Optimize scope enforcement Date: Sat, 9 Nov 2024 12:08:56 +0100 Message-ID: <20241109110856.222842-4-mic@digikod.net> In-Reply-To: <20241109110856.222842-1-mic@digikod.net> References: <20241109110856.222842-1-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/20241109110856.222842-4-mic@digikod.net Reviewed-by: Günther Noack --- Changes since v2: * Make the unix_scope variable global to the file and remove previous get_current_unix_scope_domain(). --- security/landlock/task.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/security/landlock/task.c b/security/landlock/task.c index 4acbd7c40eee..dc7dab78392e 100644 --- a/security/landlock/task.c +++ b/security/landlock/task.c @@ -204,12 +204,17 @@ static bool is_abstract_socket(struct sock *const sock) return false; } +static const struct access_masks unix_scope = { + .scope = LANDLOCK_SCOPE_ABSTRACT_UNIX_SOCKET, +}; + 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(); + landlock_get_applicable_domain(landlock_get_current_domain(), + unix_scope); /* Quick return for non-landlocked tasks. */ if (!dom) @@ -225,7 +230,8 @@ static int hook_unix_may_send(struct socket *const sock, struct socket *const other) { const struct landlock_ruleset *const dom = - landlock_get_current_domain(); + landlock_get_applicable_domain(landlock_get_current_domain(), + unix_scope); if (!dom) return 0; @@ -243,6 +249,10 @@ static int hook_unix_may_send(struct socket *const sock, return 0; } +static const struct 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 +266,7 @@ static int hook_task_kill(struct task_struct *const p, } else { dom = landlock_get_current_domain(); } + dom = landlock_get_applicable_domain(dom, signal_scope); /* Quick return for non-landlocked tasks. */ if (!dom) @@ -279,7 +290,8 @@ 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_get_applicable_domain( + landlock_file(fown->file)->fown_domain, signal_scope); /* Quick return for unowned socket. */ if (!dom)