linux-kernel - Re: [PATCH] power: domain: no need to check return value of debugfs

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:   Wed, 23 Jan 2019 09:20:05 +0100
From:   Ulf Hansson <ulf.hansson@...aro.org>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Kevin Hilman <khilman@...nel.org>,
        Len Brown <len.brown@...el.com>,
        Linux PM <linux-pm@...r.kernel.org>
Subject: Re: [PATCH] power: domain: no need to check return value of
 debugfs_create functions

On Wed, 23 Jan 2019 at 08:59, Greg Kroah-Hartman
<gregkh@...uxfoundation.org> wrote:
>
> On Wed, Jan 23, 2019 at 08:44:36AM +0100, Ulf Hansson wrote:
> > On Tue, 22 Jan 2019 at 16:23, Greg Kroah-Hartman
> > <gregkh@...uxfoundation.org> wrote:
> > >
> > > When calling debugfs functions, there is no need to ever check the
> > > return value.  The function can work or not, but the code logic should
> > > never do something different based on this.
> >
> > Doesn't this boils done to whether we want to care to check if memory
> > allocation failed?
>
> You should not care.

Okay.

>
> > Somewhere down the call chain from debugfs_create_dir(), we end up in
> > alloc_inode() and it looks like that can fail, no?
>
> Yes it can, right now it will return NULL, I'll go change that to return
> ENOMEM, but even then, your really do not care what happens as none of
> your other code flow should ever care about what debugfs does, or does
> not, do.

In that case, why don't we convert the debugfs_create_dir() and
friends, to becomes "void" functions? Or maybe that's your plan going
forward?

Kind regards
Uffe