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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31DF7C433FE for ; Thu, 11 Nov 2021 06:50:40 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B7C6761037 for ; Thu, 11 Nov 2021 06:50:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org B7C6761037 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 84912404DF; Thu, 11 Nov 2021 06:50:39 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id MMgeSAPKzwrq; Thu, 11 Nov 2021 06:50:38 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp4.osuosl.org (Postfix) with ESMTPS id 6804E404EA; Thu, 11 Nov 2021 06:50:38 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 4628BC0020; Thu, 11 Nov 2021 06:50:38 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 97907C0020 for ; Thu, 11 Nov 2021 06:50:36 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id D32A7400C9 for ; Thu, 11 Nov 2021 06:50:35 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Authentication-Results: smtp2.osuosl.org (amavisd-new); dkim=pass (2048-bit key) header.d=infradead.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 1pWWDWfxHB5Q for ; Thu, 11 Nov 2021 06:50:35 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by smtp2.osuosl.org (Postfix) with ESMTPS id 049F9400FB for ; Thu, 11 Nov 2021 06:50:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=1WOvyqEQIYPJu8OHmBDb4GQnNqqjABzGe1DFQzws+Ig=; b=X0tmSUWgTYLpDf3Ad7Y/XgybNP XhjDToP2PDAK4xYQYNSBdYoZ4LeaU351MCcWWfWklhO9n6WhJ9MmUC7KTBbu2hWOlGKOAhXObG7tb kwA/Y6WOY7va6qdeHmqBucCDXYgU79nXcDIXnsTnkJcYUjOoxeQiBsn8g94U25chJOjON1XyWMHES EsAWvAyBbD7ouV5HQalYbEIQC3F9re8UNVIUKMV8Zm90yBIe6r6jHfFFh2uxjd++ThnRHfE5Rr1Cl Njtc40MXJ9F5Yi/v84NyS25k4/9iqYVSL1hiHUe5pfcN9X+C1REl28jImp5UIA1YLN4p4OPgdnRHW 2TRAkHAA==; Received: from [2001:4bb8:19a:7ee7:dc25:8b64:278b:ff22] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1ml3uq-002Vx8-4N; Thu, 11 Nov 2021 06:50:33 +0000 From: Christoph Hellwig To: iommu@lists.linux-foundation.org Subject: [PATCH 03/11] dma-direct: always leak memory that can't be re-encrypted Date: Thu, 11 Nov 2021 07:50:19 +0100 Message-Id: <20211111065028.32761-4-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211111065028.32761-1-hch@lst.de> References: <20211111065028.32761-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Cc: Robin Murphy , David Rientjes X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" We must never unencryped memory go back into the general page pool. So if we fail to set it back to encrypted when freeing DMA memory, leak the memory insted and warn the user. Signed-off-by: Christoph Hellwig --- kernel/dma/direct.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 996ba4edb2fa3..d7a489be48470 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -84,9 +84,14 @@ static int dma_set_decrypted(struct device *dev, void *vaddr, size_t size) static int dma_set_encrypted(struct device *dev, void *vaddr, size_t size) { + int ret; + if (!force_dma_unencrypted(dev)) return 0; - return set_memory_encrypted((unsigned long)vaddr, 1 << get_order(size)); + ret = set_memory_encrypted((unsigned long)vaddr, 1 << get_order(size)); + if (ret) + pr_warn_ratelimited("leaking DMA memory that can't be re-encrypted\n"); + return ret; } static void __dma_direct_free_pages(struct device *dev, struct page *page, @@ -261,7 +266,6 @@ void *dma_direct_alloc(struct device *dev, size_t size, return ret; out_encrypt_pages: - /* If memory cannot be re-encrypted, it must be leaked */ if (dma_set_encrypted(dev, page_address(page), size)) return NULL; out_free_pages: @@ -307,7 +311,8 @@ void dma_direct_free(struct device *dev, size_t size, } else { if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED)) arch_dma_clear_uncached(cpu_addr, size); - dma_set_encrypted(dev, cpu_addr, 1 << page_order); + if (dma_set_encrypted(dev, cpu_addr, 1 << page_order)) + return; } __dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size); @@ -361,7 +366,8 @@ void dma_direct_free_pages(struct device *dev, size_t size, dma_free_from_pool(dev, vaddr, size)) return; - dma_set_encrypted(dev, vaddr, 1 << page_order); + if (dma_set_encrypted(dev, vaddr, 1 << page_order)) + return; __dma_direct_free_pages(dev, page, size); } -- 2.30.2 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu