watchdog: ziirave_wdt: check record length in ziirave_firm_verify()

[ Upstream commit 8b61d8ca751bc15875b50e0ff6ac3ba0cf95a529 ]

The "rec->len" value comes from the firmware.  We generally do
trust firmware, but it's always better to double check.  If
the length value is too large it would lead to memory corruption
when we set "data[i] = ret;"

Fixes: 217209db ("watchdog: ziirave_wdt: Add support to upload the firmware.")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/3b58b453f0faa8b968c90523f52c11908b56c346.1748463049.git.dan.carpenter@linaro.org


Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>