From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E13BEC433DF for ; Mon, 29 Jun 2020 22:00:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C11EC206C3 for ; Mon, 29 Jun 2020 22:00:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593468045; bh=0hGTAF6FQOoPxWnG+9gP2MAMKZocEFQKeDcy44MXjUY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=r3T907q392xM5tbXqmEYYIRoprC90Ge0N0G9tHTDaFXX/VgpcTSI5AhN6K4Z9r8KH 1ipiqhVcSlYKP+vwV9bWSnbE/GiFtZAIt0WYCC6+Nll1H3B547D+qbEbkP3yYasK0e hzDqscSCxK6PpixYyOhfqhBz7v9/BRQQsX5BkVWY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404694AbgF2WAo (ORCPT ); Mon, 29 Jun 2020 18:00:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:56906 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726336AbgF2SfY (ORCPT ); Mon, 29 Jun 2020 14:35:24 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6413223CD1; Mon, 29 Jun 2020 15:20:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593444017; bh=0hGTAF6FQOoPxWnG+9gP2MAMKZocEFQKeDcy44MXjUY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zhIfCLHwQjFi/C6dS+slQpnDApLd86pClN+kSfbZBxczLaZp3Pba2lZL6ShoPOX46 E4eLUT0CLtJzTT39P0n5AJGjm+SAdr6X0J7IgZ2w66gzYv+MN4JMqkzNv0wj7mOaOz YER7agwW+zz2gtQZNAFRel615hHYvZCkEXs+pdJQ= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: David Rientjes , Christoph Hellwig , Sasha Levin Subject: [PATCH 5.7 123/265] dma-direct: check return value when encrypting or decrypting memory Date: Mon, 29 Jun 2020 11:15:56 -0400 Message-Id: <20200629151818.2493727-124-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200629151818.2493727-1-sashal@kernel.org> References: <20200629151818.2493727-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.7.7-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.7.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.7.7-rc1 X-KernelTest-Deadline: 2020-07-01T15:14+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Rientjes [ Upstream commit 56fccf21d1961a06e2a0c96ce446ebf036651062 ] __change_page_attr() can fail which will cause set_memory_encrypted() and set_memory_decrypted() to return non-zero. If the device requires unencrypted DMA memory and decryption fails, simply free the memory and fail. If attempting to re-encrypt in the failure path and that encryption fails, there is no alternative other than to leak the memory. Fixes: c10f07aa27da ("dma/direct: Handle force decryption for DMA coherent buffers in common code") Signed-off-by: David Rientjes Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin --- kernel/dma/direct.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 4e789c46ff0bf..98c445dcb308b 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -124,6 +124,7 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, { struct page *page; void *ret; + int err; if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && dma_alloc_need_uncached(dev, attrs) && @@ -176,8 +177,12 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, } ret = page_address(page); - if (force_dma_unencrypted(dev)) - set_memory_decrypted((unsigned long)ret, 1 << get_order(size)); + if (force_dma_unencrypted(dev)) { + err = set_memory_decrypted((unsigned long)ret, + 1 << get_order(size)); + if (err) + goto out_free_pages; + } memset(ret, 0, size); @@ -196,9 +201,13 @@ done: return ret; out_encrypt_pages: - if (force_dma_unencrypted(dev)) - set_memory_encrypted((unsigned long)page_address(page), - 1 << get_order(size)); + if (force_dma_unencrypted(dev)) { + err = set_memory_encrypted((unsigned long)page_address(page), + 1 << get_order(size)); + /* If memory cannot be re-encrypted, it must be leaked */ + if (err) + return NULL; + } out_free_pages: dma_free_contiguous(dev, page, size); return NULL; -- 2.25.1