Merge "drm/msm : check buffer size before writing to user buffer"

/* Copyright (c) 2009-2017, The Linux Foundation. All rights reserved.

/* Copyright (c) 2009-2018, The Linux Foundation. All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 and

	len = sde_evtlog_dump_to_buffer(sde_dbg_base.evtlog, evtlog_buf,

			SDE_EVTLOG_BUF_MAX, true);

	if (len < 0 || len > count) {

		pr_err("len is more than user buffer size");

		return 0;

	}

	if (copy_to_user(buff, evtlog_buf, len))

		return -EFAULT;

	*ppos += len;