From: "Jürgen Groß" <jgross@suse.com>
To: Yousef Alhouseen <alhouseenyousef@gmail.com>,
Stefano Stabellini <sstabellini@kernel.org>,
Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Cc: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 2/2] xen/gntalloc: validate grant count before allocation
Date: Wed, 1 Jul 2026 09:53:24 +0200 [thread overview]
Message-ID: <ea52ef38-8ad2-4b1f-af34-203f167242e5@suse.com> (raw)
In-Reply-To: <20260626223805.43781-3-alhouseenyousef@gmail.com>
[-- Attachment #1.1.1: Type: text/plain, Size: 665 bytes --]
On 27.06.26 00:38, Yousef Alhouseen wrote:
> gntalloc_ioctl_alloc() allocates the grant-id array before checking
> whether the requested count fits within the global grant limit. Counts
> above that limit cannot succeed, so reject them before the
> user-controlled allocation reaches kcalloc().
>
> Use a subtraction-based check while holding gref_mutex so adding the
> requested count cannot wrap. Also cast the count before advancing the
> per-file index so the page-size multiplication is performed in 64-bit
> arithmetic.
>
> Signed-off-by: Yousef Alhouseen <alhouseenyousef@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Juergen
[-- Attachment #1.1.2: OpenPGP public key --]
[-- Type: application/pgp-keys, Size: 3743 bytes --]
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 495 bytes --]
prev parent reply other threads:[~2026-07-01 7:53 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-06-24 12:47 [PATCH] " Yousef Alhouseen
2026-06-26 12:14 ` Juergen Gross
2026-06-26 22:38 ` [PATCH v2 0/2] " Yousef Alhouseen
2026-06-26 22:38 ` [PATCH v2 1/2] xen/gntalloc: make grant counters unsigned Yousef Alhouseen
2026-07-01 7:52 ` Jürgen Groß
2026-06-26 22:38 ` [PATCH v2 2/2] xen/gntalloc: validate grant count before allocation Yousef Alhouseen
2026-07-01 7:53 ` Jürgen Groß [this message]
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=ea52ef38-8ad2-4b1f-af34-203f167242e5@suse.com \
--to=jgross@suse.com \
--cc=alhouseenyousef@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=oleksandr_tyshchenko@epam.com \
--cc=sstabellini@kernel.org \
--cc=xen-devel@lists.xenproject.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
all inboxes | Powered by JetHome®