From patchwork Mon Apr 20 08:11:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 11498369 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5AD2E81 for ; Mon, 20 Apr 2020 08:11:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3973F21D79 for ; Mon, 20 Apr 2020 08:11:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587370298; bh=z7HimAurwDR3lrdQ6oem6FxF/SwH+vDNz6rygcWxpxQ=; h=From:To:Cc:Subject:Date:List-ID:From; b=bD0PWR8Af4E5HJopMJCu854hO9wwuUVoe5NoSq3M1+alSHHXmZ84j8myXfGn/emoj XcR6MeL1GGfulHLM+Uc4eOnCByribxWcFB5FtqF5rbXnxfTzDep5O7iH6B1lFHYsd/ YOLpOr8RSolgbazZy8o1uRvM8/4Gz3K1jAzvwY0Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725865AbgDTILh (ORCPT ); Mon, 20 Apr 2020 04:11:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:47174 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725773AbgDTILh (ORCPT ); Mon, 20 Apr 2020 04:11:37 -0400 Received: from e123331-lin.home (amontpellier-657-1-18-247.w109-210.abo.wanadoo.fr [109.210.65.247]) (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 2D3E320A8B; Mon, 20 Apr 2020 08:11:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587370297; bh=z7HimAurwDR3lrdQ6oem6FxF/SwH+vDNz6rygcWxpxQ=; h=From:To:Cc:Subject:Date:From; b=fqeCK0wgi2aU5Kupe7LuDEmWEQPXPlbM26SWTyXAt61zJnlCOF7Q6QvovjM95cVYa CllOGZycz/aXP3lwbWBwQ/yCTnl1PtSFfZlIKLhmiGoKgHUgGNiDh5Ya+UprL1JM8N 3DRgCuWkDnCvcu+M76vMzB0Mg0Bil/nxRq2UtVz8= From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Cc: linux-acpi@vger.kernel.org, sudeep.holla@arm.com, guohanjun@huawei.com, lorenzo.pieralisi@arm.com, Ard Biesheuvel Subject: [PATCH] acpi: arm64/iort: Ensure DMA mask does not exceed device limit Date: Mon, 20 Apr 2020 10:11:31 +0200 Message-Id: <20200420081131.16822-1-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org When calculating the DMA mask from the address limit provided by the firmware, we add one to the ilog2() of the end address, and pass the result to DMA_BIT_MASK(). For an end address that is not a power-of-2 minus 1, this will result in the mask to be wider than the limit, and cover memory that is not addressable by the device. Instead, we should add 1 to 'end' before taking the log, so that a limit of, say, 0x3fffffff gets translated to a mask of 30, but any value below it gets translated to 29. Signed-off-by: Ard Biesheuvel --- drivers/acpi/arm64/iort.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 7d04424189df..aab2f51eff14 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -1162,7 +1162,7 @@ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) * firmware. */ end = dmaaddr + size - 1; - mask = DMA_BIT_MASK(ilog2(end) + 1); + mask = DMA_BIT_MASK(ilog2(end + 1)); dev->bus_dma_limit = end; dev->coherent_dma_mask = mask; *dev->dma_mask = mask;