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 750EFC76190 for ; Fri, 26 Jul 2019 13:45:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E67E22CE4 for ; Fri, 26 Jul 2019 13:45:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564148706; bh=tTGj7TxV+qZskt12DE672FS4M46Bp/vOTZu0gwHaCJc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Snx/Vm0pOM7CPTy8U8m3YcBmC+YYFtrKSXmUwfUd4t68TGobOdHmnSt5759NkUNvA jBfWVDtQia4kI246fdf9nJuyHBP83o9oK2DgpHgalSHzhnEgvzhwSFNqz2B019B2/U DYIhMo8so6jWKJWeZ/m3RgWqAqqn4CD+8bame2ms= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388504AbfGZNpE (ORCPT ); Fri, 26 Jul 2019 09:45:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:53588 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388487AbfGZNpC (ORCPT ); Fri, 26 Jul 2019 09:45:02 -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 627FA22CC2; Fri, 26 Jul 2019 13:45:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564148701; bh=tTGj7TxV+qZskt12DE672FS4M46Bp/vOTZu0gwHaCJc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BlCXobIu8+RczhbEEY7jpHStrKYS6/h19C8/SFl4LBMq98IciOZGv5aojBtYEK5/v uHcOkcv2I1WlCAPbGZ/dg99qy1IGtGPPexZYGFp+YOjA0uBcRNXS4j6x51WKLAGwUC 1bpAYUHJJDGwn+uREgTzJ08uz68YsKDdzBu3HASc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Doug Berger , Michal Nazarewicz , Yue Hu , Mike Rapoport , Laura Abbott , Peng Fan , Thomas Gleixner , Marek Szyprowski , Andrey Konovalov , Andrew Morton , Linus Torvalds , Sasha Levin , linux-mm@kvack.org Subject: [PATCH AUTOSEL 4.9 19/30] mm/cma.c: fail if fixed declaration can't be honored Date: Fri, 26 Jul 2019 09:44:21 -0400 Message-Id: <20190726134432.12993-19-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190726134432.12993-1-sashal@kernel.org> References: <20190726134432.12993-1-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: Doug Berger [ Upstream commit c633324e311243586675e732249339685e5d6faa ] The description of cma_declare_contiguous() indicates that if the 'fixed' argument is true the reserved contiguous area must be exactly at the address of the 'base' argument. However, the function currently allows the 'base', 'size', and 'limit' arguments to be silently adjusted to meet alignment constraints. This commit enforces the documented behavior through explicit checks that return an error if the region does not fit within a specified region. Link: http://lkml.kernel.org/r/1561422051-16142-1-git-send-email-opendmb@gmail.com Fixes: 5ea3b1b2f8ad ("cma: add placement specifier for "cma=" kernel parameter") Signed-off-by: Doug Berger Acked-by: Michal Nazarewicz Cc: Yue Hu Cc: Mike Rapoport Cc: Laura Abbott Cc: Peng Fan Cc: Thomas Gleixner Cc: Marek Szyprowski Cc: Andrey Konovalov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- mm/cma.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/mm/cma.c b/mm/cma.c index 4ea0f32761c1..7cb569a188c4 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -268,6 +268,12 @@ int __init cma_declare_contiguous(phys_addr_t base, */ alignment = max(alignment, (phys_addr_t)PAGE_SIZE << max_t(unsigned long, MAX_ORDER - 1, pageblock_order)); + if (fixed && base & (alignment - 1)) { + ret = -EINVAL; + pr_err("Region at %pa must be aligned to %pa bytes\n", + &base, &alignment); + goto err; + } base = ALIGN(base, alignment); size = ALIGN(size, alignment); limit &= ~(alignment - 1); @@ -298,6 +304,13 @@ int __init cma_declare_contiguous(phys_addr_t base, if (limit == 0 || limit > memblock_end) limit = memblock_end; + if (base + size > limit) { + ret = -EINVAL; + pr_err("Size (%pa) of region at %pa exceeds limit (%pa)\n", + &size, &base, &limit); + goto err; + } + /* Reserve memory */ if (fixed) { if (memblock_is_region_reserved(base, size) || -- 2.20.1