From nobody Thu Apr 2 07:43:56 2026 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.9]) (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 2B3EF26ED35; Mon, 30 Mar 2026 03:08:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.9 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774840117; cv=none; b=irMtHr09vGlw+Xcb6yJBqCe/Fqq5DTi+9lDXMNYGGFfBWNErCxVpCs5MDREfjAPpuibdiw7Ef+Vs1PuNwySj0r03EKuUeEuVnJas7J/q0GKUM8+x2eINP+i0iW2RM48MjsowpSiTw0/w69xZ32a/hguYRkzMQ1pRdYrUlTAl0Zw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774840117; c=relaxed/simple; bh=mcEVOJ2LG3KT7zONZb6BF8om4Uq2uTeYaEizPU+/NBE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=GtsFs5B0VHzW0v4ORSF7pf9cCS/5uBOefCDGgzpzdjF/n6vtc83B4JlqxX+3V8YDQL4EVRsNbXRG1vcdBOGAx9rpNzLOcmxtsdEAlWlx3uR+vAV0lKviSozGItY3HIzmhIVhl43E7Dw/LfxzznZy1GEydfUeoVUKoOzS0nAZEAI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=ACPiVoY2; arc=none smtp.client-ip=192.198.163.9 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="ACPiVoY2" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1774840116; x=1806376116; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=mcEVOJ2LG3KT7zONZb6BF8om4Uq2uTeYaEizPU+/NBE=; b=ACPiVoY20nZCi22gtkY/fKFVBE7XVah7onbo8BlM07gvIzm7IyJsJYuT xrVr3UVhmuYfuOEuRCxqkf5prYWpJAt+9jVWHOW7jccdFfyzPIQtoKVrE Yq2ILzndu1ZFSliz49Cp02lE6sQMCH3xyG8ip9lRd79kBHRj9xYFaY52r Ho2XancGeZnIFnpyz5hpeEnQjcD2vK+thRJhBPdUfw6L+3rvcLJj92mXx jwDLy0vquDSbAViXp6ROLEhGFkacTYuOuzDF5kiQU9kfNYThmt7YW8jmQ yySpSHvIRxRGTWsxQZsEz5dMhd8nIqGX18wULeiDa23H/urYQbD/yO+F+ A==; X-CSE-ConnectionGUID: gBQVLZGvTZud53Jnvv0bQA== X-CSE-MsgGUID: rc/pYEedTYK0fGKEyZUemg== X-IronPort-AV: E=McAfee;i="6800,10657,11743"; a="86517932" X-IronPort-AV: E=Sophos;i="6.23,149,1770624000"; d="scan'208";a="86517932" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by fmvoesa103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Mar 2026 20:08:35 -0700 X-CSE-ConnectionGUID: 4letKbCoRZecnFtED8Tt2Q== X-CSE-MsgGUID: zdxweSVWTpK9Z6OblDc3nw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,149,1770624000"; d="scan'208";a="221052606" Received: from spr-duan.bj.intel.com ([172.16.114.123]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Mar 2026 20:08:33 -0700 From: Zhenzhong Duan To: iommu@lists.linux.dev, linux-kernel@vger.kernel.org Cc: jgg@ziepe.ca, kevin.tian@intel.com, joro@8bytes.org, will@kernel.org, robin.murphy@arm.com, baolu.lu@linux.intel.com, Zhenzhong Duan , stable@vger.kernel.org Subject: [PATCH] iommufd: Fix return value of iommufd_fault_fops_write() Date: Sun, 29 Mar 2026 23:07:55 -0400 Message-ID: <20260330030755.12856-1-zhenzhong.duan@intel.com> X-Mailer: git-send-email 2.47.3 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" copy_from_user() may return number of bytes failed to copy, we should not pass over this number to user space to cheat that write() succeed. Instead, -EFAULT should be returned. Cc: stable@vger.kernel.org Fixes: 07838f7fd529 ("iommufd: Add iommufd fault object") Signed-off-by: Zhenzhong Duan Reviewed-by: Lu Baolu Reviewed-by: Kevin Tian Reviewed-by: Pranjal Shrivastava Reviewed-by: Shuai Xue --- drivers/iommu/iommufd/eventq.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/iommufd/eventq.c b/drivers/iommu/iommufd/eventq.c index f1e686b3a265..710eef0b6004 100644 --- a/drivers/iommu/iommufd/eventq.c +++ b/drivers/iommu/iommufd/eventq.c @@ -187,9 +187,10 @@ static ssize_t iommufd_fault_fops_write(struct file *f= ilep, const char __user *b =20 mutex_lock(&fault->mutex); while (count > done) { - rc =3D copy_from_user(&response, buf + done, response_size); - if (rc) + if (copy_from_user(&response, buf + done, response_size)) { + rc =3D -EFAULT; break; + } =20 static_assert((int)IOMMUFD_PAGE_RESP_SUCCESS =3D=3D (int)IOMMU_PAGE_RESP_SUCCESS); --=20 2.47.3