BugLink: https://bugs.launchpad.net/bugs/1845038

[ Upstream commit 3b5f307e ]

While loading fw crashdump in function fw_crash_buffer_show(), left bytes
in one dma chunk was not checked, if copying size over it, overflow access
will cause kernel panic.
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Acked-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>