From: Kees Cook <keescook@chromium.org>
To: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>,
Mimi Zohar <zohar@linux.ibm.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-fsdevel@vger.kernel.org, Hao Sun <sunhao.th@gmail.com>,
stable@vger.kernel.org
Subject: Re: [PATCH] vfs: Check fd has read access in kernel_read_file_from_fd()
Date: Thu, 7 Oct 2021 16:39:16 -0700 [thread overview]
Message-ID: <202110071639.1CBFCF1@keescook> (raw)
In-Reply-To: <20211007220110.600005-1-willy@infradead.org>
On Thu, Oct 07, 2021 at 11:01:10PM +0100, Matthew Wilcox (Oracle) wrote:
> If we open a file without read access and then pass the fd to a syscall
> whose implementation calls kernel_read_file_from_fd(), we get a warning
> from __kernel_read():
>
> if (WARN_ON_ONCE(!(file->f_mode & FMODE_READ)))
>
> This currently affects both finit_module() and kexec_file_load(), but
> it could affect other syscalls in the future.
>
> Reported-by: Hao Sun <sunhao.th@gmail.com>
> Fixes: b844f0ecbc56 ("vfs: define kernel_copy_file_from_fd()")
> Cc: stable@vger.kernel.org
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Thanks for chasing this down!
--
Kees Cook
next prev parent reply other threads:[~2021-10-07 23:39 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-07 22:01 [PATCH] vfs: Check fd has read access in kernel_read_file_from_fd() Matthew Wilcox (Oracle)
2021-10-07 23:39 ` Kees Cook [this message]
2021-10-11 8:54 ` Christian Brauner
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=202110071639.1CBFCF1@keescook \
--to=keescook@chromium.org \
--cc=akpm@linux-foundation.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=stable@vger.kernel.org \
--cc=sunhao.th@gmail.com \
--cc=viro@zeniv.linux.org.uk \
--cc=willy@infradead.org \
--cc=zohar@linux.ibm.com \
/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).