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From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>,
	Ulf Hansson <ulf.hansson@linaro.org>, Gary R Hook <ghook@amd.com>,
	Heiko Carstens <heiko.carstens@de.ibm.com>
Subject: Re: [PATCH 2/2] debugfs: return error values, not NULL
Date: Wed, 23 Jan 2019 11:29:30 +0100	[thread overview]
Message-ID: <20190123102930.GC17123@kroah.com> (raw)
In-Reply-To: <20190123102814.GB17123@kroah.com>

On Wed, Jan 23, 2019 at 11:28:14AM +0100, Greg Kroah-Hartman wrote:
> When an error happens, debugfs should return an error pointer value, not
> NULL.  This will prevent the totally theoretical error where a debugfs
> call fails due to lack of memory, returning NULL, and that dentry value
> is then passed to another debugfs call, which would end up succeeding,
> creating a file at the root of the debugfs tree, but would then be
> impossible to remove (because you can not remove the directory NULL).
> 
> So, to make everyone happy, always return errors, this makes the users
> of debugfs much simpler (they do not have to ever check the return
> value), and everyone can rest easy.
> 
> Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
> Reported-by: Ulf Hansson <ulf.hansson@linaro.org>
> Reported-by: Gary R Hook <ghook@amd.com>
> Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>

Oops, also reported by:
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>

I'll go fix that up when I merge this.

greg k-h

  reply	other threads:[~2019-01-23 10:29 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-01-23 10:27 [PATCH 1/2] debugfs: fix debugfs_rename parameter checking Greg Kroah-Hartman
2019-01-23 10:28 ` [PATCH 2/2] debugfs: return error values, not NULL Greg Kroah-Hartman
2019-01-23 10:29   ` Greg Kroah-Hartman [this message]
2019-01-23 10:31     ` Greg Kroah-Hartman
2019-01-23 11:06   ` Michal Hocko
2019-01-23 11:55     ` Greg Kroah-Hartman
2019-01-23 12:13       ` Michal Hocko
2019-01-23 12:26         ` Greg Kroah-Hartman
2019-01-23 12:40           ` Michal Hocko
2019-01-23 13:00             ` Greg Kroah-Hartman
2019-01-23 13:09               ` Michal Hocko
2019-01-23 13:40                 ` Greg Kroah-Hartman
2019-01-23 13:49                   ` Greg Kroah-Hartman
2019-01-23 13:54                   ` Michal Hocko
2019-01-23 21:32   ` Sebastian Andrzej Siewior
2019-01-24  2:26   ` Masami Hiramatsu
2019-01-28 13:55     ` Masami Hiramatsu
2019-01-28 16:04       ` Greg Kroah-Hartman

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