strongarm: mask off high[31:28] bits from dir and state registers

The high[31:28] bits of 'direction' and 'state' registers of
SA-1100/SA-1110 device are reserved. Setting them may lead to
OOB 's->handler[]' array access issue. Mask off [31:28] bits to
avoid it.

Reported-by: Moguofang <moguofang@huawei.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-id: 20181030114635.31232-1-ppandit@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/hw/arm/strongarm.c b/hw/arm/strongarm.c
index ec2627374d070abda2f3564aeeddb090042a61ab..644a9c45b4ecb1f3dfaa21c9932ed3b3b58daf12 100644 (file)
--- a/hw/arm/strongarm.c
+++ b/hw/arm/strongarm.c
@@ -587,12 +587,12 @@ static void strongarm_gpio_write(void *opaque, hwaddr offset,
 
     switch (offset) {
     case GPDR:        /* GPIO Pin-Direction registers */
-        s->dir = value;
+        s->dir = value & 0x0fffffff;
         strongarm_gpio_handler_update(s);
         break;
 
     case GPSR:        /* GPIO Pin-Output Set registers */
-        s->olevel |= value;
+        s->olevel |= value & 0x0fffffff;
         strongarm_gpio_handler_update(s);
         break;