public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Greg KH <gregkh@linuxfoundation.org>
To: Wentao Liang <vulab@iscas.ac.cn>
Cc: tj@kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] kernfs: fix potential NULL dereference in mmap handler
Date: Tue, 1 Apr 2025 16:51:13 +0100	[thread overview]
Message-ID: <2025040117-flock-narrow-3b19@gregkh> (raw)
In-Reply-To: <20250401151859.2842-1-vulab@iscas.ac.cn>

On Tue, Apr 01, 2025 at 11:18:59PM +0800, Wentao Liang wrote:
> The kernfs_fop_mmap() invokes the '->mmap' callback without verifying its
> existence. This leads to a NULL pointer dereference when the kernfs node
> does not define the operation, resulting in an invalid memory access.

How can that happen with any in-kernel user of kernfs?  If you try to
mmap any sysfs file today does this trigger?

thanks,

greg k-h

      parent reply	other threads:[~2025-04-01 15:52 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-01 15:18 [PATCH] kernfs: fix potential NULL dereference in mmap handler Wentao Liang
2025-04-01 15:50 ` Tejun Heo
2025-04-01 15:51 ` Greg KH [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=2025040117-flock-narrow-3b19@gregkh \
    --to=gregkh@linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=tj@kernel.org \
    --cc=vulab@iscas.ac.cn \
    /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