linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: David Laight <David.Laight@ACULAB.COM>
To: 'Karel Zak' <kzak@redhat.com>,
	Eugene Korenevsky <ekorenevsky@gmail.com>,
	Davidlohr Bueso <dave@stgolabs.net>,
	"linux-efi@vger.kernel.org" <linux-efi@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Ard Biesheuvel <ard.biesheuvel@linaro.org>
Subject: RE: [PATCH v2] efi: take size of partition entry from GPT header
Date: Thu, 13 Sep 2018 13:06:13 +0000	[thread overview]
Message-ID: <6d349d22d37041c1a2942d8ed4c76b69@AcuMS.aculab.com> (raw)
In-Reply-To: <20180912083844.iegei2kobcz4b7ag@ws.net.home>

From: Karel Zak
> Sent: 12 September 2018 09:39
> On Tue, Sep 11, 2018 at 07:15:27PM +0300, Eugene Korenevsky wrote:
> > +static gpt_entry *get_gpt_entry(gpt_header *gpt_hdr, gpt_entry *ptes, u32 index)
> > +{
> > +	return (gpt_entry *)((u8 *)ptes + gpt->sizeof_partition_entry * index);
> 
> I guess header use LE, so you need:
> 
>                le32_to_cpu(gpt_hdr->sizeof_partition_entry)

I suspect you also need a sanity check that the value isn't too small
or stupidly large.

In principle slightly short lengths presumably imply that the disk
was formatted with an older standard - so the last fields should be
ignored.
They may not be any such disks - until the on-disk structure is extended
and the kernel structure updated to match.

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)


  reply	other threads:[~2018-09-13 13:04 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-11 16:15 [PATCH v2] efi: take size of partition entry from GPT header Eugene Korenevsky
2018-09-11 16:27 ` Davidlohr Bueso
2018-09-11 16:42   ` Eugene Korenevsky
2018-09-11 22:56 ` kbuild test robot
2018-09-11 22:59 ` Ard Biesheuvel
2018-09-11 23:20 ` kbuild test robot
2018-09-12  8:38 ` Karel Zak
2018-09-13 13:06   ` David Laight [this message]
2018-09-13 19:48     ` Eugene Korenevsky
2018-09-14  9:01       ` David Laight
2018-09-14 11:07         ` kzak
2018-10-06 18:41           ` Eugene Korenevsky
2018-10-08 11:15             ` Karel Zak

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6d349d22d37041c1a2942d8ed4c76b69@AcuMS.aculab.com \
    --to=david.laight@aculab.com \
    --cc=ard.biesheuvel@linaro.org \
    --cc=dave@stgolabs.net \
    --cc=ekorenevsky@gmail.com \
    --cc=kzak@redhat.com \
    --cc=linux-efi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).