linux-kernel - Re: [PATCH v4 4/5] mtd_blkdevs: add option to enable scanning for partitions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Y21ZXRKJF3hZg8wk@makrotopia.org>
Date:   Thu, 10 Nov 2022 20:04:45 +0000
From:   Daniel Golle <daniel@...rotopia.org>
To:     Richard Weinberger <richard@....at>
Cc:     Jens Axboe <axboe@...nel.dk>,
        Miquel Raynal <miquel.raynal@...tlin.com>,
        Vignesh Raghavendra <vigneshr@...com>,
        Davidlohr Bueso <dave@...olabs.net>,
        Matthew Wilcox <willy@...radead.org>,
        "Martin K. Petersen" <martin.petersen@...cle.com>,
        Chaitanya Kulkarni <kch@...dia.com>,
        Ming Lei <ming.lei@...hat.com>,
        linux-block <linux-block@...r.kernel.org>,
        linux-kernel <linux-kernel@...r.kernel.org>,
        linux-mtd <linux-mtd@...ts.infradead.org>,
        linux-efi <linux-efi@...r.kernel.org>
Subject: Re: [PATCH v4 4/5] mtd_blkdevs: add option to enable scanning for
 partitions

On Thu, Nov 10, 2022 at 08:44:53PM +0100, Richard Weinberger wrote:
> ----- Ursprüngliche Mail -----
> > Von: "Daniel Golle" <daniel@...rotopia.org>
> > +
> > +		if (!IS_ENABLED(CONFIG_MTD_BLOCK_PARTITIONS) || mtd_type_is_nand(new->mtd))
> > +			gd->flags |= GENHD_FL_NO_PART;
> 
> I know that NAND should not get used with mtdblock because lack of wearleveling and
> in general too many writes. But what exactly is the rationale to deny part scanning for NAND?

As UBI should be used on NAND, partition scanning should be enabled for
ubiblock devices to have uImage.FIT filesystem subimages mapped by the
partition parser.

If not skipping partition scanning on NAND-backed mtdblock devices the
scanning itself will already trigger multiple warnings which now happen
every time when a NAND-backed mtdblock device is being opened since
commit 96a3295c ("mtdblock: warn if opened on NAND").