linux-kernel - Re: [PATCH v4 5/6] ipc: Clamp semmni to the real IPCMNI limit

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 12 Mar 2018 16:59:59 -0400
From:   Waiman Long <longman@...hat.com>
To:     "Luis R. Rodriguez" <mcgrof@...nel.org>
Cc:     Kees Cook <keescook@...omium.org>, linux-kernel@...r.kernel.org,
        linux-fsdevel@...r.kernel.org,
        Andrew Morton <akpm@...ux-foundation.org>,
        Al Viro <viro@...iv.linux.org.uk>,
        Matthew Wilcox <willy@...radead.org>
Subject: Re: [PATCH v4 5/6] ipc: Clamp semmni to the real IPCMNI limit

On 03/12/2018 04:52 PM, Luis R. Rodriguez wrote:
> On Mon, Mar 12, 2018 at 04:15:43PM -0400, Waiman Long wrote:
>> +	if (clamped)
>> +		pr_warn_once("sysctl: \"sem[3]\" was set out of range [%d, %d], clamped to %d.\n",
>> +			     0, IPCMNI, ns->sc_semmni);
> Why warn if the kernel already does that? If we can avoid more code on
> drivers the better.
>
>   Luis

As said before, this case is special because "sem" is a collection of 4
different values. The last one is semmni which I tries to apply the same
range clamping here, whereas the other 3 are left as they are. The
standard proc_dointvec_minmax() handler cannot be used here because of
that. I will clarify that in the commit log.

Cheers,
Longman