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Date: Tue, 20 Sep 2016 11:45:11 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Shailendra Verma <shailendra.v@samsung.com>
Cc: Jarod Wilson <jarod@wilsonet.com>,
        Mauro Carvalho Chehab <mchehab@osg.samsung.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-media@vger.kernel.org, devel@driverdev.osuosl.org,
        Ravikant Sharma <ravikant.s2@samsung.com>, vidushi.koul@samsung.com,
        linux-kernel@vger.kernel.org
Subject: Re: Staging: Media: Lirc - Fix possible ERR_PTR() dereferencing.
Message-ID: <20160920084510.GG13620@mwanda>
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On Tue, Sep 20, 2016 at 12:21:21PM +0530, Shailendra Verma wrote:
> This is of course wrong to call kfree() if memdup_user() fails,
> no memory was allocated and the error in the error-valued pointer
> should be returned.
> 
> Reviewed-by: Ravikant Sharma <ravikant.s2@samsung.com>
> Signed-off-by: Shailendra Verma <shailendra.v@samsung.com>

Calling kfree(NULL) is fine so there is no bug in the original code.
Also this patch creates a new locking bug.

regards,
dan carpenter