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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 39187C432BE for ; Fri, 13 Aug 2021 23:54:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DD21E610FE for ; Fri, 13 Aug 2021 23:54:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org DD21E610FE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 8A4B88D0009; Fri, 13 Aug 2021 19:54:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 854CA8D0003; Fri, 13 Aug 2021 19:54:47 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 743438D0009; Fri, 13 Aug 2021 19:54:47 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0006.hostedemail.com [216.40.44.6]) by kanga.kvack.org (Postfix) with ESMTP id 5A5008D0003 for ; Fri, 13 Aug 2021 19:54:47 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 0854F1694D for ; Fri, 13 Aug 2021 23:54:47 +0000 (UTC) X-FDA: 78471715014.22.0AFDEEF Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf07.hostedemail.com (Postfix) with ESMTP id B4B6510001FF for ; Fri, 13 Aug 2021 23:54:46 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 99DDE610C8; Fri, 13 Aug 2021 23:54:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1628898886; bh=xN7uDkzQLv00XCsVvFZ+jfprpbgZTkT5VePR68D5fjg=; h=Date:From:To:Subject:In-Reply-To:From; b=0Me4an+Bt+HDevKlYVe1zaS8IgnSZQuWWxz1J/wF6o6xoSX7A2Iq1cg9u87u63rur OIXy7smYGKQ3t6Hc3vKoewJ/36jr/ITAYJZGzvHuWLB1F0WYmg3InFngSvcTW54iI1 UzHxRkT45WPXKHRsxAvJSUyF9vFe+l8LMNuW1tSE= Date: Fri, 13 Aug 2021 16:54:45 -0700 From: Andrew Morton To: akpm@linux-foundation.org, gregkh@linuxfoundation.org, linux-mm@kvack.org, linux@armlinux.org.uk, mcgrof@kernel.org, mm-commits@vger.kernel.org, nixiaoming@huawei.com, palmerdabbelt@google.com, stable@vger.kernel.org, torvalds@linux-foundation.org, wangkefeng.wang@huawei.com, wangliang101@huawei.com Subject: [patch 7/7] lib: use PFN_PHYS() in devmem_is_allowed() Message-ID: <20210813235445.iSOZmfuWE%akpm@linux-foundation.org> In-Reply-To: <20210813165350.dc9afa56d27eadbd8ce629c0@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: B4B6510001FF Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=0Me4an+B; spf=pass (imf07.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspamd-Server: rspam01 X-Stat-Signature: p4utakho16c1tjsdoga3pjr65tirj9un X-HE-Tag: 1628898886-508130 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Liang Wang Subject: lib: use PFN_PHYS() in devmem_is_allowed() The physical address may exceed 32 bits on 32-bit systems with more than 32 bits of physcial address. Use PFN_PHYS() in devmem_is_allowed(), or the physical address may overflow and be truncated. We found this bug when mapping a high addresses through devmem tool, when CONFIG_STRICT_DEVMEM is enabled on the ARM with ARM_LPAE and devmem is used to map a high address that is not in the iomem address range, an unexpected error indicating no permission is returned. This bug was initially introduced from v2.6.37, and the function was moved to lib when v5.11. Link: https://lkml.kernel.org/r/20210731025057.78825-1-wangliang101@huawei.com Fixes: 087aaffcdf9c ("ARM: implement CONFIG_STRICT_DEVMEM by disabling access to RAM via /dev/mem") Fixes: 527701eda5f1 ("lib: Add a generic version of devmem_is_allowed()") Signed-off-by: Liang Wang Reviewed-by: Luis Chamberlain Cc: Palmer Dabbelt Cc: Greg Kroah-Hartman Cc: Russell King Cc: Liang Wang Cc: Xiaoming Ni Cc: Kefeng Wang Cc: [2.6.37+] Signed-off-by: Andrew Morton --- lib/devmem_is_allowed.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/lib/devmem_is_allowed.c~lib-use-pfn_phys-in-devmem_is_allowed +++ a/lib/devmem_is_allowed.c @@ -19,7 +19,7 @@ */ int devmem_is_allowed(unsigned long pfn) { - if (iomem_is_exclusive(pfn << PAGE_SHIFT)) + if (iomem_is_exclusive(PFN_PHYS(pfn))) return 0; if (!page_is_ram(pfn)) return 1; _