From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 8C66158FD10 for ; Fri, 11 Sep 2026 20:05:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789157150; cv=none; b=JQYta0tUpSyeMONnvjHlN9ZZqN6Zk6dOct98D4S1TmJoaBuVRGTNC3K8VU1GVbqaKpBJYjlACm5x2enODJEB8EFxKVs5GNic3d4t6DQDxH+Ov8HEo+aDCZ/8XUQx7dObCROB7t2jMeilAHkBKV5wZJ3DLuf9N2JB8dm54hwpXFE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789157150; c=relaxed/simple; bh=DLVrTAfyPDfb82inEYjx0vNmDh3f6HMrip2qBcFhSp8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=GQsW1cHPtOeFFEGJ98gqTLmoocEXqUVuGqdKlqGNhVQdJUxLw5Q4zN+1rJdtBxJe2tK5Wrxz2g1ELX8WhjxOpyj4aIzQXpPuWWnYmPMhTmjct7Eih8CekJP24d5icHZF4RJ/RNd2dFy2OQWqpSu02RpTWu6xtkVpZswdSJYZLFE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1bQRX+u0; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="1bQRX+u0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 022201F00898; Fri, 11 Sep 2026 20:05:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789157142; bh=mj/USPqcd8Dh3N7V+E+sRLXHSosYyu+ZbUusdnG8CGE=; h=From:To:Cc:Subject:Date:Reply-To; b=1bQRX+u0YxK4OSGXKt/ucNVC5r4fzQVSHnNZ6VZqbVac9WhyWfGouopBOtPMbagX1 f0rLa9V60tbypm7u1fYn8390ukW/7HQqPuDS0Q5/M9wh3jn/vUEfMx+kz0RxcTeszB PSvMqNune8eCPjnRDsn/E/EwqwNffx8JT4XhU45s= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89751: x86/tdx: Fix off-by-one in port I/O handling Date: Fri, 11 Sep 2026 21:47:20 +0200 Message-ID: <2026091107-CVE-2026-89751-e5cf@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2541; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=xjWcos7HnGqNVpZH6gpb7T9qgUkrayFurkt23PUUrVo=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIvv5q/6ulylyV1291e3P5M4pdlFLTp9d5/HMYNviW 8btN/RbO2JZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAim+0ZFixOCNt0dcOPEMUd Pnf/TDq/J4ddVpJhfh7fG34fIevVS5vWFFV4mXiVR5f2AwA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: x86/tdx: Fix off-by-one in port I/O handling handle_in() and handle_out() in arch/x86/coco/tdx/tdx.c use: u64 mask = GENMASK(BITS_PER_BYTE * size, 0); GENMASK(h, l) includes bit h. For size=1 (INB), this produces GENMASK(8, 0) = 0x1FF (9 bits) instead of GENMASK(7, 0) = 0xFF (8 bits). The mask is one bit too wide for all I/O sizes. Fix the mask calculation. The Linux kernel CVE team has assigned CVE-2026-89751 to this issue. Affected and fixed versions =========================== Issue introduced in 5.19 with commit 03149948832a078f759022ed5b92e722d8d23c26 and fixed in 6.12.109 with commit 222b7005e4519f633b4cd666226256abbab46a1a Issue introduced in 5.19 with commit 03149948832a078f759022ed5b92e722d8d23c26 and fixed in 6.18.50 with commit c4a22154870813d10aa0b4c734a574c726f9d4b0 Issue introduced in 5.19 with commit 03149948832a078f759022ed5b92e722d8d23c26 and fixed in 7.2.4 with commit bb45f705c4440dd3c689328319b88dd28770bbb8 Issue introduced in 5.19 with commit 03149948832a078f759022ed5b92e722d8d23c26 and fixed in 7.3-rc1 with commit 0f63e656b1c679d32ac595de29d10c03efca6a25 Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-89751 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: arch/x86/coco/tdx/tdx.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/222b7005e4519f633b4cd666226256abbab46a1a https://git.kernel.org/stable/c/c4a22154870813d10aa0b4c734a574c726f9d4b0 https://git.kernel.org/stable/c/bb45f705c4440dd3c689328319b88dd28770bbb8 https://git.kernel.org/stable/c/0f63e656b1c679d32ac595de29d10c03efca6a25