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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3EF67ECAAD5 for ; Thu, 8 Sep 2022 06:57:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231163AbiIHG5Y (ORCPT ); Thu, 8 Sep 2022 02:57:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229663AbiIHG5X (ORCPT ); Thu, 8 Sep 2022 02:57:23 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2F4C90C56 for ; Wed, 7 Sep 2022 23:57:22 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 1CDB561B7C for ; Thu, 8 Sep 2022 06:57:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22FC6C433C1; Thu, 8 Sep 2022 06:57:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1662620241; bh=RKj0p7+2DV/jN/iA6U4WYLQVoMCZshcyv2vDEmRBeAo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=pzlCI3AR14y4reXJ0jTJZ2rn5kWNEscL5/QYctNJYCYvmijtkfyM6OX9OMlQfkHkx u9CCf4liu5qODolVl6EIhLuqfkNVhsOnayE1Qt1opWUf2gnXqKBzPEV5XB5BGHYkfJ 9p2yn8+BU8Db0gy/2EMO3Bl+r0Uzcrxnu7fhqKpjpa97emZdeQVNUxO1owEwl2HCEG uavSMmAL7Q2ckUKI/ZmORqVWqLDBVR9vj0niuISEBSwe91FwkIud2cThoaGBH5nkJI RNx82ugPhxUj03wXqjqJA0kZ79GDbbKllJrBSyCzJyjUKJQHgRZbTMFX/xQ2N5bX2E yB3t4aNVng5fA== Date: Thu, 8 Sep 2022 07:57:16 +0100 From: Lee Jones To: Dan Carpenter Cc: Andy Shevchenko , ChiYuan Huang , Matthias Brugger , ChiaEn Wu , linux-arm Mailing List , "moderated list:ARM/Mediatek SoC support" , kernel-janitors Subject: Re: [PATCH] mfd: mt6370: add bounds checking to regmap_read/write functions Message-ID: References: <20220822125705.GD2695@kadam> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220822125705.GD2695@kadam> Precedence: bulk List-ID: X-Mailing-List: kernel-janitors@vger.kernel.org On Mon, 22 Aug 2022, Dan Carpenter wrote: > On Fri, Aug 19, 2022 at 09:27:13AM +0300, Andy Shevchenko wrote: > > On Fri, Aug 19, 2022 at 8:25 AM Dan Carpenter wrote: > > > > > > It looks like there are a potential out of bounds accesses in the > > > read/write() functions. Also can "len" be negative? Let's check for > > > that too. > > > > ... > > > > > Fixes: ab9905c5e38e ("mfd: mt6370: Add MediaTek MT6370 support") > > > > > From static analysis. This code is obviously harmless however it may > > > not be required. The regmap range checking is slightly complicated and > > > I haven't remembered where all it's done. > > > > Exactement! I do not think this Fixes anything, I believe you are > > adding a dead code. So, can you do deeper analysis? > > I spent a long time looking at this code before I sent it and I've > spent a long time looking at it today. > > Smatch said that these values come from the user, but now it seems > less clear to me and I have rebuilt the DB so I don't have the same > information I was looking at earlier. > > So I can't see if these come from the user but neither can I find any > bounds checking. What's the consensus please? -- Lee Jones [李琼斯] 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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 683E2C38145 for ; Thu, 8 Sep 2022 06:58:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=L/0R12EVxRgpX4kFQ8nl1eESACCRJd1KxnTVhCPA8Tk=; b=ut49rQ5kB3nukQ xuoiEkfuRy/4TlG6FCzHcuPJrisWtr9+uCuTYDarbt05P/rzMZ2dXMSe3ub7krckdotNmHs41IXWM pefO8Xjj98fIZdcc+jOeBekswu4WAKLthb73EbBw6X0H8fWc8OcIkldk6hgQiCb6OCfsugUHuSrkv 6W9e7em3Gz61oIfBiLqqNSpRZig4Q9nlLuTFB/957vZeXdn2y50Nog1qy1aXCm1rrZ4tfQq2i7nIG J+5DH0duQYMj6VMZEhL1Gdc4cWWQZH1zF6Jdb+DHILpCx4t1uAJDCJvMBZuLyjTwzcBxRf9TtxjWY e9SMb2J5B7fHvGUWzteg==; 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charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gTW9uLCAyMiBBdWcgMjAyMiwgRGFuIENhcnBlbnRlciB3cm90ZToKCj4gT24gRnJpLCBBdWcg MTksIDIwMjIgYXQgMDk6Mjc6MTNBTSArMDMwMCwgQW5keSBTaGV2Y2hlbmtvIHdyb3RlOgo+ID4g T24gRnJpLCBBdWcgMTksIDIwMjIgYXQgODoyNSBBTSBEYW4gQ2FycGVudGVyIDxkYW4uY2FycGVu dGVyQG9yYWNsZS5jb20+IHdyb3RlOgo+ID4gPgo+ID4gPiBJdCBsb29rcyBsaWtlIHRoZXJlIGFy ZSBhIHBvdGVudGlhbCBvdXQgb2YgYm91bmRzIGFjY2Vzc2VzIGluIHRoZQo+ID4gPiByZWFkL3dy aXRlKCkgZnVuY3Rpb25zLiAgQWxzbyBjYW4gImxlbiIgYmUgbmVnYXRpdmU/ICBMZXQncyBjaGVj ayBmb3IKPiA+ID4gdGhhdCB0b28uCj4gPiAKPiA+IC4uLgo+ID4gCj4gPiA+IEZpeGVzOiBhYjk5 MDVjNWUzOGUgKCJtZmQ6IG10NjM3MDogQWRkIE1lZGlhVGVrIE1UNjM3MCBzdXBwb3J0IikKPiA+ IAo+ID4gPiBGcm9tIHN0YXRpYyBhbmFseXNpcy4gIFRoaXMgY29kZSBpcyBvYnZpb3VzbHkgaGFy bWxlc3MgaG93ZXZlciBpdCBtYXkKPiA+ID4gbm90IGJlIHJlcXVpcmVkLiAgVGhlIHJlZ21hcCBy YW5nZSBjaGVja2luZyBpcyBzbGlnaHRseSBjb21wbGljYXRlZCBhbmQKPiA+ID4gSSBoYXZlbid0 IHJlbWVtYmVyZWQgd2hlcmUgYWxsIGl0J3MgZG9uZS4KPiA+IAo+ID4gRXhhY3RlbWVudCEgSSBk byBub3QgdGhpbmsgdGhpcyBGaXhlcyBhbnl0aGluZywgSSBiZWxpZXZlIHlvdSBhcmUKPiA+IGFk ZGluZyBhIGRlYWQgY29kZS4gU28sIGNhbiB5b3UgZG8gZGVlcGVyIGFuYWx5c2lzPwo+IAo+IEkg c3BlbnQgYSBsb25nIHRpbWUgbG9va2luZyBhdCB0aGlzIGNvZGUgYmVmb3JlIEkgc2VudCBpdCBh bmQgSSd2ZQo+IHNwZW50IGEgbG9uZyB0aW1lIGxvb2tpbmcgYXQgaXQgdG9kYXkuCj4gCj4gU21h dGNoIHNhaWQgdGhhdCB0aGVzZSB2YWx1ZXMgY29tZSBmcm9tIHRoZSB1c2VyLCBidXQgbm93IGl0 IHNlZW1zCj4gbGVzcyBjbGVhciB0byBtZSBhbmQgSSBoYXZlIHJlYnVpbHQgdGhlIERCIHNvIEkg ZG9uJ3QgaGF2ZSB0aGUgc2FtZQo+IGluZm9ybWF0aW9uIEkgd2FzIGxvb2tpbmcgYXQgZWFybGll ci4KPiAKPiBTbyBJIGNhbid0IHNlZSBpZiB0aGVzZSBjb21lIGZyb20gdGhlIHVzZXIgYnV0IG5l aXRoZXIgY2FuIEkgZmluZCBhbnkKPiBib3VuZHMgY2hlY2tpbmcuCgpXaGF0J3MgdGhlIGNvbnNl bnN1cyBwbGVhc2U/CgotLSAKTGVlIEpvbmVzIFvmnY7nkLzmlq9dCgpfX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwpsaW51eC1hcm0ta2VybmVsIG1haWxpbmcg bGlzdApsaW51eC1hcm0ta2VybmVsQGxpc3RzLmluZnJhZGVhZC5vcmcKaHR0cDovL2xpc3RzLmlu ZnJhZGVhZC5vcmcvbWFpbG1hbi9saXN0aW5mby9saW51eC1hcm0ta2VybmVsCg==