From: kenkinming2002@gmail.com
To: Benjamin Tissoires <bentiss@kernel.org>
Cc: jikos@kernel.org, linux-input@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] HID: i2c-hid: fix potential buffer overflow in i2c_hid_get_report()
Date: Thu, 8 Jan 2026 00:08:22 +0800 [thread overview]
Message-ID: <aV5_76eRrcGJ1ehE@anonymous> (raw)
In-Reply-To: <or6uoheepcbcx4sm36g7z3ccevhjn6iv2ddztx6mpw4qgbdoyo@n3yfbkwlye5i>
On Wed, Jan 07, 2026 at 03:20:13PM +0100, Benjamin Tissoires wrote:
> It makes sense to put this min call here, but it's already present at
> line 304 a few lines after. Could you remove that second check (and
> unnecessary one after your change).
The min call at line 304 uses ret_count which comes from the first 2
bytes in the device response and indicates the actual size of the
returned report descriptor. Notice that importantly ret_count can be
strictly smaller than ihid->bufsize because persumably not all reports
have the same size. The behavior will change if the caller provides a
larger buffer than is necessary. With the min call at line 304, we will
return the actual size of the report descriptor (without the 2 bytes
length header). Without the min call at 304, we will instead return the
size of supplied buffer.
Yours sincerely,
Ken Kwok
next prev parent reply other threads:[~2026-01-07 16:08 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-31 18:18 [PATCH] HID: i2c-hid: fix potential buffer overflow in i2c_hid_get_report() Kwok Kin Ming
2026-01-07 14:20 ` Benjamin Tissoires
2026-01-07 16:08 ` kenkinming2002 [this message]
2026-01-07 17:37 ` Benjamin Tissoires
2026-01-07 17:36 ` Benjamin Tissoires
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=aV5_76eRrcGJ1ehE@anonymous \
--to=kenkinming2002@gmail.com \
--cc=bentiss@kernel.org \
--cc=jikos@kernel.org \
--cc=linux-input@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