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=-9.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 68FA9C43610 for ; Tue, 13 Nov 2018 05:51:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 282902251E for ; Tue, 13 Nov 2018 05:51:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="HvdJ+1aV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 282902251E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732206AbeKMPrv (ORCPT ); Tue, 13 Nov 2018 10:47:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:33718 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732167AbeKMPru (ORCPT ); Tue, 13 Nov 2018 10:47:50 -0500 Received: from sasha-vm.mshome.net (unknown [64.114.255.114]) (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 AD7CC2250E; Tue, 13 Nov 2018 05:51:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542088282; bh=7mQEjIV2IFnljtef90NPlS5B4LarDbNuW7HZDt0nVlo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HvdJ+1aV8KYlkDGo8BjZILp8xpzc7dsasGNKaxZgxO5atzzcy0aHEvMJ9xINP0+uy 1xFS3GDEotbQpAGkpZdOy8MoVmYwPPIiQ1u+Nt2RbUG4n+domF6iy7tjQmijMV2p4Y GD0fZ5roKQSDa12pwgmoXXPrxQUCGLAaRL6gSWLo= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Dan Carpenter , Stephen Rothwell , Keith Busch , "Michael S. Tsirkin" , Kees Cook , YueHaibing , Andrew Morton , Linus Torvalds , Sasha Levin , linux-mm@kvack.org Subject: [PATCH AUTOSEL 4.18 16/39] mm/gup_benchmark.c: prevent integer overflow in ioctl Date: Tue, 13 Nov 2018 00:50:30 -0500 Message-Id: <20181113055053.78352-16-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181113055053.78352-1-sashal@kernel.org> References: <20181113055053.78352-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Carpenter [ Upstream commit 4b408c74ee5a0b74fc9265c2fe39b0e7dec7c056 ] The concern here is that "gup->size" is a u64 and "nr_pages" is unsigned long. On 32 bit systems we could trick the kernel into allocating fewer pages than expected. Link: http://lkml.kernel.org/r/20181025061546.hnhkv33diogf2uis@kili.mountain Fixes: 64c349f4ae78 ("mm: add infrastructure for get_user_pages_fast() benchmarking") Signed-off-by: Dan Carpenter Acked-by: Kirill A. Shutemov Reviewed-by: Andrew Morton Cc: Stephen Rothwell Cc: Keith Busch Cc: "Michael S. Tsirkin" Cc: Kees Cook Cc: YueHaibing Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- mm/gup_benchmark.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c index 7405c9d89d65..7e6f2d2dafb5 100644 --- a/mm/gup_benchmark.c +++ b/mm/gup_benchmark.c @@ -23,6 +23,9 @@ static int __gup_benchmark_ioctl(unsigned int cmd, int nr; struct page **pages; + if (gup->size > ULONG_MAX) + return -EINVAL; + nr_pages = gup->size / PAGE_SIZE; pages = kvcalloc(nr_pages, sizeof(void *), GFP_KERNEL); if (!pages) -- 2.17.1