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From: Johan Hovold <johan@kernel.org>
To: Oliver Neukum <oneukum@suse.com>
Cc: Johan Hovold <johan@kernel.org>,
	linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] USB: serial: fix invalid user-pointer checks
Date: Tue, 8 Nov 2016 16:41:17 +0100	[thread overview]
Message-ID: <20161108154117.GN2664@localhost> (raw)
In-Reply-To: <1478614393.2168.2.camel@suse.com>

On Tue, Nov 08, 2016 at 03:13:13PM +0100, Oliver Neukum wrote:
> On Tue, 2016-11-08 at 13:26 +0100, Johan Hovold wrote:
> > Drop invalid user-pointer checks from ioctl handlers.
> > 
> > A NULL-pointer can be valid in user space and copy_to_user() takes
> > care
> > of sanity checking.
> 
> Shouldn't we bail out early in these cases?

I don't think it's worth it, and this is also the general pattern for
such ioctls. The added overhead for an error case like this is really
negligible.

Thanks,
Johan

  reply	other threads:[~2016-11-08 15:41 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-11-08 12:26 [PATCH] USB: serial: fix invalid user-pointer checks Johan Hovold
2016-11-08 14:13 ` Oliver Neukum
2016-11-08 15:41   ` Johan Hovold [this message]
2016-11-09 10:58     ` Oliver Neukum
2016-11-09 11:07       ` Johan Hovold

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