[PATCH v2] virtio_scsi: Add validation for residual bytes from response

[Xie Yongji]

This ensures that the residual bytes in response (might come
from an untrusted device) will not exceed the data buffer length.

Signed-off-by: Xie Yongji <xieyongji@xxxxxxxxxxxxx>
Acked-by: Jason Wang <jasowang@xxxxxxxxxx>
---
 drivers/scsi/virtio_scsi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index b9c86a7e3b97..2badc3c80d73 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -97,7 +97,7 @@ static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev)
 static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid)
 {
 	if (resid)
-		scsi_set_resid(sc, resid);
+		scsi_set_resid(sc, min(resid, scsi_bufflen(sc)));
 }
 
 /*
-- 
2.11.0