From: Al Viro <viro@zeniv.linux.org.uk>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kees Cook <keescook@chromium.org>,
Andrew Morton <akpm@linux-foundation.org>,
Michal Hocko <mhocko@suse.com>,
Alexey Dobriyan <adobriyan@gmail.com>,
Lee Duncan <lduncan@suse.com>, Chris Leech <cleech@redhat.com>,
Adam Nichols <adam@grimm-co.com>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-hardening@vger.kernel.org
Subject: Re: [PATCH v2] seq_file: Unconditionally use vmalloc for buffer
Date: Tue, 16 Mar 2021 12:43:12 +0000 [thread overview]
Message-ID: <YFCn4ERBMGoqxvUU@zeniv-ca.linux.org.uk> (raw)
In-Reply-To: <YFBdQmT64c+2uBRI@kroah.com>
On Tue, Mar 16, 2021 at 08:24:50AM +0100, Greg Kroah-Hartman wrote:
> > Completely agreed. seq_get_buf() should be totally ripped out.
> > Unfortunately, this is going to be a long road because of sysfs's ATTR
> > stuff, there are something like 5000 callers, and the entire API was
> > designed to avoid refactoring all those callers from
> > sysfs_kf_seq_show().
>
> What is wrong with the sysfs ATTR stuff? That should make it so that we
> do not have to change any caller for any specific change like this, why
> can't sysfs or kernfs handle it automatically?
Hard to tell, since that would require _finding_ the sodding ->show()
instances first. Good luck with that, seeing that most of those appear
to come from templates-done-with-cpp...
AFAICS, Kees wants to protect against ->show() instances stomping beyond
the page size. What I don't get is what do you get from using seq_file
if you insist on doing raw access to the buffer rather than using
seq_printf() and friends. What's the point?
next prev parent reply other threads:[~2021-03-16 12:53 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-15 17:48 [PATCH v2] seq_file: Unconditionally use vmalloc for buffer Kees Cook
2021-03-15 18:33 ` Al Viro
2021-03-15 20:43 ` Kees Cook
2021-03-16 7:24 ` Greg Kroah-Hartman
2021-03-16 12:43 ` Al Viro [this message]
2021-03-16 12:55 ` Greg Kroah-Hartman
2021-03-16 13:01 ` Michal Hocko
2021-03-16 19:18 ` Kees Cook
2021-03-17 10:44 ` Greg Kroah-Hartman
2021-03-16 8:31 ` Michal Hocko
2021-03-16 19:08 ` Kees Cook
2021-03-17 12:08 ` Michal Hocko
2021-03-17 13:34 ` Greg Kroah-Hartman
2021-03-17 14:44 ` Michal Hocko
2021-03-17 14:56 ` Greg Kroah-Hartman
2021-03-17 15:20 ` Michal Hocko
2021-03-17 15:38 ` Greg Kroah-Hartman
2021-03-17 15:48 ` Michal Hocko
2021-03-17 21:30 ` Kees Cook
2021-03-18 8:07 ` Greg Kroah-Hartman
2021-03-18 15:51 ` Kees Cook
2021-03-18 17:56 ` Greg Kroah-Hartman
2021-03-19 14:07 ` [seq_file] 5fd6060e50: stress-ng.eventfd.ops_per_sec -49.1% regression kernel test robot
2021-03-19 19:31 ` Kees Cook
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=YFCn4ERBMGoqxvUU@zeniv-ca.linux.org.uk \
--to=viro@zeniv.linux.org.uk \
--cc=adam@grimm-co.com \
--cc=adobriyan@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=cleech@redhat.com \
--cc=gregkh@linuxfoundation.org \
--cc=keescook@chromium.org \
--cc=lduncan@suse.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-hardening@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mhocko@suse.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).