From: Waiman Long <longman@redhat.com>
To: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
Andrew Morton <akpm@linux-foundation.org>,
Al Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH v2 2/5] sysctl: Add flags to support min/max range clamping
Date: Wed, 28 Feb 2018 13:58:53 -0500 [thread overview]
Message-ID: <e5ac80d5-2919-8944-293d-ee9b70f6ad02@redhat.com> (raw)
In-Reply-To: <20180228184325.GJ14069@wotan.suse.de>
On 02/28/2018 01:43 PM, Luis R. Rodriguez wrote:
> On Wed, Feb 28, 2018 at 12:53:40PM -0500, Waiman Long wrote:
>> On 02/27/2018 07:47 PM, Luis R. Rodriguez wrote:
>>> On Tue, Feb 27, 2018 at 03:49:48PM -0500, Waiman Long wrote:
>>>> When minimum/maximum values are specified for a sysctl parameter in
>>>> the ctl_table structure with proc_dointvec_minmax() handler,
>>> an
>>>
>>>> update
>>>> to that parameter will fail with error if the given value is outside
>>>> of the required range.
>>>>
>>>> There are use cases where it may be better to clamp the value of
>>>> the sysctl parameter to the given range without failing the update,
>>>> especially if the users are not aware of the actual range limits.
>>> Makes me wonder if we should add something which does let one query
>>> for the ranges. Then scripts can fetch that as well.
>> That will actually be better than printing out the range in the dmesg
>> log. However, I haven't figured out an easy way of doing that. If you
>> have any suggestion, please let me know about it.
> I think a macro that also adds yet another proc read-only entry with a postfix
> "_range" with an internal handler which prints the range may suffice.
>
> Luis
I think that is a possible solution. Instead of adding a macro, I will
add one more flag which does the magic when the ctl_table entry is being
processed. I think that will be simpler from the user point of view.
Cheers,
Longman
next prev parent reply other threads:[~2018-02-28 18:58 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-27 20:49 [PATCH v2 0/5] ipc: Clamp *mni to the real IPCMNI limit Waiman Long
2018-02-27 20:49 ` [PATCH v2 1/5] sysctl: Add kdoc comments to do_proc_do{u}intvec_minmax_conv_param Waiman Long
2018-02-27 21:10 ` Matthew Wilcox
2018-02-27 21:52 ` Waiman Long
2018-02-27 20:49 ` [PATCH v2 2/5] sysctl: Add flags to support min/max range clamping Waiman Long
2018-02-28 0:47 ` Luis R. Rodriguez
2018-02-28 17:53 ` Waiman Long
2018-02-28 18:43 ` Luis R. Rodriguez
2018-02-28 18:58 ` Waiman Long [this message]
2018-02-28 19:06 ` Luis R. Rodriguez
2018-03-01 17:40 ` Waiman Long
2018-02-27 20:49 ` [PATCH v2 3/5] sysctl: Warn when a clamped sysctl parameter is set out of range Waiman Long
2018-02-28 0:57 ` Luis R. Rodriguez
2018-02-28 17:55 ` Waiman Long
2018-02-27 20:49 ` [PATCH v2 4/5] ipc: Clamp msgmni and shmmni to the real IPCMNI limit Waiman Long
2018-02-28 1:01 ` Luis R. Rodriguez
2018-02-28 17:56 ` Waiman Long
2018-02-27 20:49 ` [PATCH v2 5/5] ipc: Clamp semmni " Waiman Long
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=e5ac80d5-2919-8944-293d-ee9b70f6ad02@redhat.com \
--to=longman@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=keescook@chromium.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mcgrof@kernel.org \
--cc=viro@zeniv.linux.org.uk \
/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).