From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vladis Dronov , Sinclair Yeh Subject: [PATCH 4.4 70/90] drm/vmwgfx: limit the number of mip levels in vmw_gb_surface_define_ioctl() Date: Mon, 12 Jun 2017 17:26:16 +0200 Message-Id: <20170612152601.201489417@linuxfoundation.org> In-Reply-To: <20170612152556.133240249@linuxfoundation.org> References: <20170612152556.133240249@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vladis Dronov commit ee9c4e681ec4f58e42a83cb0c22a0289ade1aacf upstream. The 'req->mip_levels' parameter in vmw_gb_surface_define_ioctl() is a user-controlled 'uint32_t' value which is used as a loop count limit. This can lead to a kernel lockup and DoS. Add check for 'req->mip_levels'. References: https://bugzilla.redhat.com/show_bug.cgi?id=1437431 Signed-off-by: Vladis Dronov Reviewed-by: Sinclair Yeh Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c @@ -1293,6 +1293,9 @@ int vmw_gb_surface_define_ioctl(struct d if (req->multisample_count != 0) return -EINVAL; + if (req->mip_levels > DRM_VMW_MAX_MIP_LEVELS) + return -EINVAL; + if (unlikely(vmw_user_surface_size == 0)) vmw_user_surface_size = ttm_round_pot(sizeof(*user_srf)) + 128;