Date: Tue, 05 Dec 2017 09:47:13 -0600
Message-ID: <20171205094713.Horde.5_tExSIcsBR4JvXtQE8cQcW@gator4166.hostgator.com>
From: "Gustavo A. R. Silva" <garsilva@embeddedor.com>
To: Ville =?utf-8?b?U3lyasOkbMOk?= <ville.syrjala@linux.intel.com>
Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>,
        Sinclair Yeh <syeh@vmware.com>,
        Thomas Hellstrom <thellstrom@vmware.com>,
        David Airlie <airlied@linux.ie>, linux-kernel@vger.kernel.org,
        dri-devel@lists.freedesktop.org
Subject: Re: [PATCH] drm/vmwgfx_kms: Fix potential NULL pointer dereference
References: <20171204215418.GA23874@embeddedor.com>
 <20171205133019.GS10981@intel.com>
In-Reply-To: <20171205133019.GS10981@intel.com>
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Hi Ville,

Quoting Ville Syrjälä <ville.syrjala@linux.intel.com>:

> On Mon, Dec 04, 2017 at 03:54:18PM -0600, Gustavo A. R. Silva wrote:
>> crtc_state is being null checked in a previous code block, which implies
>> that such pointer might be null.
>>
>> crtc_state is dereferenced in drm_atomic_helper_check_plane_state, hence
>> there is a potential null pointer dereference.
>
> This is a false positive. drm_atomic_helper_check_plane_state() will not
> dereference crtc_state when plane_state->crtc is NULL.
>

You are right.

Thank you for clarifying.
--
Gustavo A. R. Silva