commit 844817e4 upstream.

The report passed to us from transport driver could potentially be
arbitrarily large, therefore we better sanity-check it so that raw_data
that we hold in picolcd_pending structure are always kept within proper
bounds.
Reported-by: Steven Vittitoe <scvitti@google.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
[lizf: Backported to 3.4: adjust filename]
Signed-off-by: Zefan Li <lizefan@huawei.com>