From patchwork Mon Feb 24 22:52:46 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Xu X-Patchwork-Id: 13989036 Received: from mail-pl1-f171.google.com (mail-pl1-f171.google.com [209.85.214.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4FD6620D4FC for ; Mon, 24 Feb 2025 22:52:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.171 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740437577; cv=none; b=LkXUSD8GsjWJH09iHaaIstZxKQRqsd+vhiF39GfUUi8T9ZgOyd8EqI3lL0yb4wbd/h6dZ4QUdC2LB7hQt0omE0/EC08Q3X0jxeYlCWKxKK/muQelWq0E6cfb0P/RDqUMX0x9xisD63p4oohcASAInOgHqFnqjw9q9Qbsq1e4XcQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740437577; c=relaxed/simple; bh=wCBUro8X74PEVZGjy8/v6ioiKNk+ksES9zc6oIeICgg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=t9ORhqDeY/O8X4t4VFWksqlPbMgdOQOHsQFyBMM/f4FvT9EjpjDl1kAU6SauehYPofYBAx6FScTYZtJywMuabmECjKxLwHBcY9j3/GnwP3e/W/SWgjDE1YOLUWk5K8ixPURJWaDL14jTswsO+UylWqrNVTWOA5qAx9K71pQ+hVE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=Gdfh3RDM; arc=none smtp.client-ip=209.85.214.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Gdfh3RDM" Received: by mail-pl1-f171.google.com with SMTP id d9443c01a7336-2217875d103so11454425ad.3 for ; Mon, 24 Feb 2025 14:52:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1740437574; x=1741042374; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=JC+iCaenVWT1qC+wv1WYjnvGE2KwlNSxR7B2FLEJRHA=; b=Gdfh3RDMuL/f58E3rRMPSXDE481hOe7+hkV6sRSuAeK3oTMFbI5ngWeB0Co7L4y5mZ aimwR4seqrWPPgUf64FJDsh0aRci5+XZd6w4m1Htz3tCk2PTmH3OXypx/+QMcIaOEoJx Xk7S0m+RnbXMHNpt5NjlWW9lvB5bk7VbAa9jE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740437574; x=1741042374; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=JC+iCaenVWT1qC+wv1WYjnvGE2KwlNSxR7B2FLEJRHA=; b=aOq+y9WeK38J98PfK6TP218VjHW371zjUCiHInqLBprkeCQoCuhlF9ws0bbBJj6vY3 ASVVfUVtI3WhnuQ9v3l74uR9Vvb+IXOKX5Xuz3dAezNzcGG8yRf9OcVd2A2FiMnkgCl+ /XAPFk8RmF1P/jpSMOKiLWlPwPyvRaHVZsGNyfAB+cX7CshBdyM4QC3sCNu5lUec0XFb vNzlKhAnJojR/gNCQs0lq/o9j/oX0jju4ChY7aCt4CAiKP9zFPn1c7WpEAotcRtrk/TJ Q4f0mHIaNTwJYasdUIk6PHLURrI9/0GjnZwTVK8LduYDXhpkRCJ2PeY9emB0zN0EKr5o pi+Q== X-Forwarded-Encrypted: i=1; AJvYcCVWvjIJq0cPQdp6Umz+KtXpwa/ZgUV95dBvOl/wPkY6t4FRAiq1Wd2FAqhKxdV5wfPjTLxWGa5EYN+uqQpA78k=@vger.kernel.org X-Gm-Message-State: AOJu0Ywmn7BhfTtl73Dfe7hdpjRP5SYq6Iq5jR6A1LaaWucvkEFufkue 6rNo6D21cGaRulnk9v38B66xGZIHRG2lZRcYYxJls7JLtYlp+mffIp6MEercTA== X-Gm-Gg: ASbGnctgB2lEGLPfZbjMoH04bQCI3dBmllLQy2KLXpAAPzHuX/C2Jwrw9WQXksej6lD y34GEjQboLqK7rufw1m2bPdWOegonhF6oUIqe1+qyrdLpfhpOA7oYJ0FfjRr1sXUJk0I0GiNGOA mXjh5vBqLTajUUJenp/lqPY5yb8dK10o3gFk73IzGyb31mXSzOrnbc9ZQukfzxZs38JFvNaYwVI uMUqk+jT3TO2ALGP7JX5CWHG4Jj/z5xyYZULAFYoCRo2WP9hQKyTh9kcWO2GuaPcBmyQlSki1ex pSxzT8x3t/yzBP7SlnVLTJsyx+3DCYq3LwHM0ziKGQpDnPlNs3jN+ds8709b X-Google-Smtp-Source: AGHT+IFWvMJ1DifgHpp00NgiU+l7P2X3hIfGn/N0QZgxCBlNaoLWIru7jUXTs0mtOdXL84lprXpfPg== X-Received: by 2002:a05:6a20:3d89:b0:1ee:d621:3c3f with SMTP id adf61e73a8af0-1eef3b1fcddmr10299435637.0.1740437574612; Mon, 24 Feb 2025 14:52:54 -0800 (PST) Received: from localhost (201.59.83.34.bc.googleusercontent.com. [34.83.59.201]) by smtp.gmail.com with UTF8SMTPSA id 41be03b00d2f7-aedaa6475dasm110603a12.54.2025.02.24.14.52.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 24 Feb 2025 14:52:54 -0800 (PST) From: jeffxu@chromium.org To: akpm@linux-foundation.org, keescook@chromium.org, jannh@google.com, torvalds@linux-foundation.org, vbabka@suse.cz, lorenzo.stoakes@oracle.com, Liam.Howlett@Oracle.com, adhemerval.zanella@linaro.org, oleg@redhat.com, avagin@gmail.com, benjamin@sipsolutions.net Cc: linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, linux-mm@kvack.org, jorgelo@chromium.org, sroettger@google.com, hch@lst.de, ojeda@kernel.org, thomas.weissschuh@linutronix.de, adobriyan@gmail.com, johannes@sipsolutions.net, pedro.falcato@gmail.com, hca@linux.ibm.com, willy@infradead.org, anna-maria@linutronix.de, mark.rutland@arm.com, linus.walleij@linaro.org, Jason@zx2c4.com, deller@gmx.de, rdunlap@infradead.org, davem@davemloft.net, peterx@redhat.com, f.fainelli@gmail.com, gerg@kernel.org, dave.hansen@linux.intel.com, mingo@kernel.org, ardb@kernel.org, mhocko@suse.com, 42.hyeyoo@gmail.com, peterz@infradead.org, ardb@google.com, enh@google.com, rientjes@google.com, groeck@chromium.org, mpe@ellerman.id.au, aleksandr.mikhalitsyn@canonical.com, mike.rapoport@gmail.com, Jeff Xu , Kees Cook Subject: [PATCH v7 7/7] mseal, system mappings: update mseal.rst Date: Mon, 24 Feb 2025 22:52:46 +0000 Message-ID: <20250224225246.3712295-8-jeffxu@google.com> X-Mailer: git-send-email 2.48.1.658.g4767266eb4-goog In-Reply-To: <20250224225246.3712295-1-jeffxu@google.com> References: <20250224225246.3712295-1-jeffxu@google.com> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Jeff Xu Update memory sealing documentation to include details about system mappings. Signed-off-by: Jeff Xu Reviewed-by: Kees Cook --- Documentation/userspace-api/mseal.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/userspace-api/mseal.rst b/Documentation/userspace-api/mseal.rst index 41102f74c5e2..10147281bf2d 100644 --- a/Documentation/userspace-api/mseal.rst +++ b/Documentation/userspace-api/mseal.rst @@ -130,6 +130,13 @@ Use cases - Chrome browser: protect some security sensitive data structures. +- System mappings: + If supported by an architecture (via CONFIG_ARCH_HAS_MSEAL_SYSTEM_MAPPINGS), + the CONFIG_MSEAL_SYSTEM_MAPPINGS seals system mappings, e.g. vdso, vvar, + uprobes, sigpage, vectors, etc. CHECKPOINT_RESTORE, UML, gVisor, rr are + known to relocate or unmap system mapping, therefore this config can't be + enabled universally. + When not to use mseal ===================== Applications can apply sealing to any virtual memory region from userspace,