[PATCH v7 03/46] mic_virtio: robust feature array size calculation

Michael S. Tsirkin
2014-11-30T15:09:43Z

mic reads sizeof(vdev->features) bits from device, but in fact it stores
bits in local features variable. use sizeof(features) to make code
robust against future changes extending sizeof(vdev->features).

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/misc/mic/card/mic_virtio.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/misc/mic/card/mic_virtio.c b/drivers/misc/mic/card/mic_virtio.c
index 4f070ad..d5da9ff 100644
--- a/drivers/misc/mic/card/mic_virtio.c
+++ b/drivers/misc/mic/card/mic_virtio.c
@@ -76,8 +76,7 @@ static u32 mic_get_features(struct virtio_device *vdev)
u8 __iomem *in_features = mic_vq_features(desc);
int feature_len = ioread8(&desc->feature_len);

- bits = min_t(unsigned, feature_len,
- sizeof(vdev->features)) * 8;
+ bits = min_t(unsigned, feature_len, sizeof(features)) * 8;
for (i = 0; i < bits; i++)
if (ioread8(&in_features[i / 8]) & (BIT(i % 8)))
features |= BIT(i);
--
MST