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=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 671BAC433DF for ; Fri, 17 Jul 2020 22:47:57 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1E55B2074B for ; Fri, 17 Jul 2020 22:47:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1E55B2074B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=vt.edu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernelnewbies-bounces@kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.94) (envelope-from ) id 1jwZ8B-000843-Vq; Fri, 17 Jul 2020 18:47:03 -0400 Received: from omr1.cc.ipv6.vt.edu ([2607:b400:92:8300:0:c6:2117:b0e] helo=omr1.cc.vt.edu) by shelob.surriel.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1jwZ88-00083m-2X for Kernelnewbies@kernelnewbies.org; Fri, 17 Jul 2020 18:47:00 -0400 Received: from mr5.cc.vt.edu (mr5.cc.ipv6.vt.edu [IPv6:2607:b400:92:8400:0:72:232:758b]) by omr1.cc.vt.edu (8.14.4/8.14.4) with ESMTP id 06HMkvIt005865 for ; Fri, 17 Jul 2020 18:46:57 -0400 Received: from mail-qt1-f199.google.com (mail-qt1-f199.google.com [209.85.160.199]) by mr5.cc.vt.edu (8.14.7/8.14.7) with ESMTP id 06HMkqqu013710 for ; Fri, 17 Jul 2020 18:46:57 -0400 Received: by mail-qt1-f199.google.com with SMTP id k9so7295545qth.17 for ; Fri, 17 Jul 2020 15:46:57 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :mime-version:content-transfer-encoding:date:message-id; bh=7C5NDIFd+wx0U0rVgQ6s1pRaduLSopbuJz9+Ghi4fTU=; b=dorVwvYrTp7nJmAbmZxIxgrxM0F48tp/DVFyRvsgpZBDyiMthIBTFjog3BL8X/3GCY sNncDsJQYUR6fxRIhR2HWo6WcQU6RYuEVJSnTFHHeYyr03fVm5tWEiBQkS77qoFURFwG FJWP+ZFQiHpSZ+3x06dX3vD/duYJSF27ONd4jUGPyc1iVIOdipJX637Yt2AVwu4C66vL RnvERQd5k9LVB3HZgFHORaS68bjm/Hf5Dlj0Mbt/IEINwIcam3QEu/Czk+YAOoA+1aG/ XGKu2/3AVziHb9hgFtdfdNccOO8GmdcC1w28i1PCL0mRQ3VjNtivqDg26qREMnYO245q f00A== X-Gm-Message-State: AOAM532wvhOz5sQVfclOx1i+M4vuKcCs4djnx7vmj0pzsLlFWdR5IfU/ Yr/s16xfCTZdlp5Sq+y5sh+fjNMFn20JNBgDuUzNNlCPNcFnhKjigCJ42oaq6ouAr6A75v913ri U+JMfqJFejTzE1hMLAwybC06NhJLNoShCb47K+fM= X-Received: by 2002:a05:620a:b1a:: with SMTP id t26mr11206049qkg.473.1595026012152; Fri, 17 Jul 2020 15:46:52 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzBY/68EODxYPEafr7DORNCtb51/q2HH5ntYrEn6NqVIfrOIfgQllBAxxmIJk5hZ3MWPeyjBA== X-Received: by 2002:a05:620a:b1a:: with SMTP id t26mr11206030qkg.473.1595026011720; Fri, 17 Jul 2020 15:46:51 -0700 (PDT) Received: from turing-police ([2601:5c0:c001:c9e1::359]) by smtp.gmail.com with ESMTPSA id o4sm13175132qtf.92.2020.07.17.15.46.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Jul 2020 15:46:48 -0700 (PDT) From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Google-Original-From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev To: Richard Sailer Subject: Re: Dubios pointer casting with put_user() In-Reply-To: References: Mime-Version: 1.0 Date: Fri, 17 Jul 2020 18:46:46 -0400 Message-ID: <96764.1595026006@turing-police> Cc: kernelnewbies X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1399219203879625260==" Errors-To: kernelnewbies-bounces@kernelnewbies.org --===============1399219203879625260== Content-Type: multipart/signed; boundary="==_Exmh_1595026006_72917P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit --==_Exmh_1595026006_72917P Content-Type: text/plain; charset=us-ascii On Fri, 17 Jul 2020 02:13:34 +0200, Richard Sailer said: > unsigned long. Is this (correctness and security wise) sane? Because as > I understand it put_user() determines the amount it copies from the > pointer type. > rc = put_user(amount, (int __user *)arg); If that were true, you wouldn't need to pass the 'amount' variable.... --==_Exmh_1595026006_72917P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Comment: Exmh version 2.9.0 11/07/2018 iQIVAwUBXxIqVgdmEQWDXROgAQLFgRAAmWcw+dDKDHMIE1nuMcrc+xtjOgeFvlCJ eB9rtJ+GgsRoGMwVdZeUoCQz1nyF5ZrrurpwmC2c1vwpZziUgl+LNQi4dxe26hLT ko5cupcAqrlt626KCbzcQOmFMlQoDk7FtxSN8Nsj/bV4GoBgGAlSTdQgPlLgVRZy ZyypsAe55UzX1cbfMmPzUTDZFwCUqjV+YhMccYKBKadvOIWaylQgypVEzOJdqa46 MfhsRQe5V+gTYTwPBujfnYoOBNo/6UjdOTw3CkqaKyD1y5Pa9JoWLoDFXQBSU/Le dUd3RphUYjcMax+nC1Jzof3tDg1iKNVZqf0KlI1BN5C8ILU8Imfsi3F+0xZJY5PH 8ymJNSxAD7iVHPHyWrK/dhL9PjjjRvYsbCghc+OYik2jhlg6Xa4HhhG4Y4idJqfx x6u6vI/Q5bOQ5mvbMiMdUH4q9h16RX5d9wqDr+LekX+ENjC3ol3/N7Oz2TSZaOUd mKun9aQ3rN5v1jHqd5aozGPR1bcaiGSx6KY76S0A8RdjUXtHnWWMVt5FZUJZF4ir S/Uc+n4iKHLgyHzmZGMr3B3NThqDzKga+SObe7Z4dBonWzVhT9S13tDV5djxJaXi EidjXsQBQsMyHzVk0SOyIpkkxByMFhrC84FeE1ixsEpnrYedCbgglE4eJ3Zzgjwo /0y02lOZXHo= =wF2F -----END PGP SIGNATURE----- --==_Exmh_1595026006_72917P-- --===============1399219203879625260== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies --===============1399219203879625260==--