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 10082C3A5A0 for ; Sat, 18 Apr 2020 14:55:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D974C2072B for ; Sat, 18 Apr 2020 14:55:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587221720; bh=2TFAKaSdT+EMO+YKZ/LNnCEY582EwDyXXk3/bqOThdo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=uEbQXKP8casUttS6SaWny9qu7WrlE8usS0FewiomUdK0tJNAtk0i+8lS6L+QDFv/Z p8T0WbjYzjjC98jWr5OZFw8wJoEX/GDOVJbUAA45ls6OqzxtZXdKTcqPKXiXmCOzba eWpkBCNpK+W8eRwIT7qpsv4G7LEFH5GxEzpz5MuI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728443AbgDROzT (ORCPT ); Sat, 18 Apr 2020 10:55:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:50166 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727833AbgDROlP (ORCPT ); Sat, 18 Apr 2020 10:41:15 -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 ED05122253; Sat, 18 Apr 2020 14:41:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587220874; bh=2TFAKaSdT+EMO+YKZ/LNnCEY582EwDyXXk3/bqOThdo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oblOSCOuOxuMFlmFnqdV36GerDpyP10qrKLgpf2ipE6XNowKCpMbTZa+TcksetwTJ DaMlM31k3RThyEffc9UowUZnCRPC9GW97vbm9PMLGGBXCeWaILHn4aGw0pEJ3dpM9v BfZCtQv0jZj0/QwwxPzzUk6Dy7DkfMT1gKc7uBDw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Kishon Vijay Abraham I , Christoph Hellwig , Sasha Levin , iommu@lists.linux-foundation.org Subject: [PATCH AUTOSEL 5.4 22/78] dma-direct: fix data truncation in dma_direct_get_required_mask() Date: Sat, 18 Apr 2020 10:39:51 -0400 Message-Id: <20200418144047.9013-22-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200418144047.9013-1-sashal@kernel.org> References: <20200418144047.9013-1-sashal@kernel.org> MIME-Version: 1.0 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: Kishon Vijay Abraham I [ Upstream commit cdcda0d1f8f4ab84efe7cd9921c98364398aefd7 ] The upper 32-bit physical address gets truncated inadvertently when dma_direct_get_required_mask() invokes phys_to_dma_direct(). This results in dma_addressing_limited() return incorrect value when used in platforms with LPAE enabled. Fix it here by explicitly type casting 'max_pfn' to phys_addr_t in order to prevent overflow of intermediate value while evaluating '(max_pfn - 1) << PAGE_SHIFT'. Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin --- kernel/dma/direct.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 867fd72cb2605..0a093a675b632 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -45,7 +45,8 @@ static inline dma_addr_t phys_to_dma_direct(struct device *dev, u64 dma_direct_get_required_mask(struct device *dev) { - u64 max_dma = phys_to_dma_direct(dev, (max_pfn - 1) << PAGE_SHIFT); + phys_addr_t phys = (phys_addr_t)(max_pfn - 1) << PAGE_SHIFT; + u64 max_dma = phys_to_dma_direct(dev, phys); return (1ULL << (fls64(max_dma) - 1)) * 2 - 1; } -- 2.20.1