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 94317EB64D9 for ; Tue, 4 Jul 2023 15:29:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231616AbjGDP3K (ORCPT ); Tue, 4 Jul 2023 11:29:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231528AbjGDP2h (ORCPT ); Tue, 4 Jul 2023 11:28:37 -0400 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 43BF010EA for ; Tue, 4 Jul 2023 08:28:21 -0700 (PDT) X-GND-Sasl: miquel.raynal@bootlin.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1688484499; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=cKvjqirkVFA+BNwb+44FbYBe7KMP6crTFIpQu43cGgY=; b=iqpIQ5dk7iebCcPsVughgIw60V8zQuNfjxJgtFr+44ariRfiXUvU3jwBrrLPh6hPLKK1FZ Y4KTfBaa82r2XG0FvFclSrix8rbJBLFZ0EfgqB1WmWrtGepOPOJoN3+89DiiIONOoM4ER8 ca0mvSsrtVyQwj7C3oLEniPoocrAfwHgv9i3WxMGYvLTzCOgFlmb3W3UJN/lTP/Yvpfav2 elCYPKab0cTTllKtKQbVBs0L00qRZ45xIrGhy8oGXbmpg5xA8fUoY+8uwhH5XNT7SXBI7u hPFwxCC8crVM2pnScZuRzKYCbrktb92AEQAlE38R4sHOCryq7EwMhy+gjURuRw== X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com Received: by mail.gandi.net (Postfix) with ESMTPSA id EE7D92000D; Tue, 4 Jul 2023 15:28:17 +0000 (UTC) Date: Tue, 4 Jul 2023 17:28:17 +0200 From: Miquel Raynal To: William Zhang Cc: Broadcom Kernel List , Linux MTD List , f.fainelli@gmail.com, rafal@milecki.pl, kursad.oney@broadcom.com, joel.peshkin@broadcom.com, computersforpeace@gmail.com, anand.gore@broadcom.com, dregan@mail.com, kamal.dasu@broadcom.com, tomer.yacoby@broadcom.com, dan.beygelman@broadcom.com, Florian Fainelli , linux-kernel@vger.kernel.org, Vignesh Raghavendra , Richard Weinberger , Kamal Dasu Subject: Re: [PATCH v3 4/5] mtd: rawnand: brcmnand: Fix potential out-of-bounds access in oob write Message-ID: <20230704172817.02e4cdb8@xps-13> In-Reply-To: <20230627193738.19596-5-william.zhang@broadcom.com> References: <20230627193738.19596-1-william.zhang@broadcom.com> <20230627193738.19596-5-william.zhang@broadcom.com> Organization: Bootlin X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi William, william.zhang@broadcom.com wrote on Tue, 27 Jun 2023 12:37:37 -0700: > When the oob buffer length is not in multiple of words, the oob write > function does out-of-bounds read on the oob source buffer at the last > iteration. Fix that by always checking length limit on the oob buffer > read and fill with 0xff when reaching the end of the buffer to the oob > registers. >=20 > Fixes: 27c5b17cd1b1 ("mtd: nand: add NAND driver "library" for Broadcom S= TB NAND controller") Wrong Fixes. Missing Cc stable. > Signed-off-by: William Zhang > Reviewed-by: Florian Fainelli >=20 > --- >=20 > Changes in v3: > - Fix kernel test robot sparse warning: > drivers/mtd/nand/raw/brcmnand/brcmnand.c:1500:54: sparse: expected uns= igned int [usertype] data > drivers/mtd/nand/raw/brcmnand/brcmnand.c:1500:54: sparse: got restrict= ed __be32 [usertype] >=20 > Changes in v2: > - Handle the remaining unaligned oob data after the oob data write loop >=20 > drivers/mtd/nand/raw/brcmnand/brcmnand.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) >=20 > diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/= raw/brcmnand/brcmnand.c > index ea03104692bf..407bf79cbaf4 100644 > --- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c > +++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c > @@ -1477,19 +1477,28 @@ static int write_oob_to_regs(struct brcmnand_cont= roller *ctrl, int i, > const u8 *oob, int sas, int sector_1k) > { > int tbytes =3D sas << sector_1k; > - int j; > + int j, k =3D 0; > + u32 last =3D 0xffffffff; > + u8 *plast =3D (u8 *)&last; > =20 > /* Adjust OOB values for 1K sector size */ > if (sector_1k && (i & 0x01)) > tbytes =3D max(0, tbytes - (int)ctrl->max_oob); > tbytes =3D min_t(int, tbytes, ctrl->max_oob); > =20 > - for (j =3D 0; j < tbytes; j +=3D 4) > + for (j =3D 0; (j + 3) < tbytes; j +=3D 4) Maybe a comment here as well to mention that you stop at the last iteration? Otherwise, just reading the line does not make you choice obvious. > oob_reg_write(ctrl, j, > (oob[j + 0] << 24) | > (oob[j + 1] << 16) | > (oob[j + 2] << 8) | > (oob[j + 3] << 0)); > + > + while (j < tbytes) > + plast[k++] =3D oob[j++]; > + > + if (tbytes & 0x3) > + oob_reg_write(ctrl, (tbytes & ~0x3), (__force u32)cpu_to_be32(last)); > + > return tbytes; > } > =20 Thanks, Miqu=C3=A8l