From: Ian Abbott <abbotti@mev.co.uk>
To: Thorsten Blum <thorsten.blum@linux.dev>,
H Hartley Sweeten <hsweeten@visionengravers.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jann Horn <jannh@google.com>, Jens Axboe <axboe@kernel.dk>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] comedi: Replace kcalloc + copy_from_user with memdup_array_user
Date: Wed, 17 Sep 2025 14:41:48 +0100 [thread overview]
Message-ID: <19be6d8a-e923-49ab-93e4-0996b7d3ddf2@mev.co.uk> (raw)
In-Reply-To: <20250917131349.117642-2-thorsten.blum@linux.dev>
On 17/09/2025 14:13, Thorsten Blum wrote:
> Replace kcalloc() followed by copy_from_user() with memdup_array_user()
> to improve and simplify comedi_unlocked_ioctl().
>
> No functional changes intended.
>
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
> ---
> drivers/comedi/comedi_fops.c | 13 ++++---------
> 1 file changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/comedi/comedi_fops.c b/drivers/comedi/comedi_fops.c
> index 7e2f2b1a1c36..dea698e509b1 100644
> --- a/drivers/comedi/comedi_fops.c
> +++ b/drivers/comedi/comedi_fops.c
> @@ -2284,15 +2284,10 @@ static long comedi_unlocked_ioctl(struct file *file, unsigned int cmd,
> rc = check_insnlist_len(dev, insnlist.n_insns);
> if (rc)
> break;
> - insns = kcalloc(insnlist.n_insns, sizeof(*insns), GFP_KERNEL);
> - if (!insns) {
> - rc = -ENOMEM;
> - break;
> - }
> - if (copy_from_user(insns, insnlist.insns,
> - sizeof(*insns) * insnlist.n_insns)) {
> - rc = -EFAULT;
> - kfree(insns);
> + insns = memdup_array_user(insnlist.insns, insnlist.n_insns,
> + sizeof(*insns));
> + if (IS_ERR(insns)) {
> + rc = PTR_ERR(insns);
> break;
> }
> rc = do_insnlist_ioctl(dev, insns, insnlist.n_insns, file);
Looks good to me. Thanks!
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
--
-=( Ian Abbott <abbotti@mev.co.uk> || MEV Ltd. is a company )=-
-=( registered in England & Wales. Regd. number: 02862268. )=-
-=( Regd. addr.: S11 & 12 Building 67, Europa Business Park, )=-
-=( Bird Hall Lane, STOCKPORT, SK3 0XA, UK. || www.mev.co.uk )=-
prev parent reply other threads:[~2025-09-17 14:36 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-17 13:13 Thorsten Blum
2025-09-17 13:41 ` Ian Abbott [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=19be6d8a-e923-49ab-93e4-0996b7d3ddf2@mev.co.uk \
--to=abbotti@mev.co.uk \
--cc=axboe@kernel.dk \
--cc=gregkh@linuxfoundation.org \
--cc=hsweeten@visionengravers.com \
--cc=jannh@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=thorsten.blum@linux.dev \
/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®