[media] dvb-core: prevent some corruption the legacy ioctl

[uclinux-h8/linux.git] / drivers / media / dvb-core / dvb_frontend.c

diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c
index b30ca59..842b9c8 100644 (file)
--- a/drivers/media/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb-core/dvb_frontend.c
@@ -2384,7 +2384,13 @@ static int dvb_frontend_ioctl_legacy(struct file *file,
 
        case FE_DISEQC_SEND_MASTER_CMD:
                if (fe->ops.diseqc_send_master_cmd) {
-                       err = fe->ops.diseqc_send_master_cmd(fe, (struct dvb_diseqc_master_cmd*) parg);
+                       struct dvb_diseqc_master_cmd *cmd = parg;
+
+                       if (cmd->msg_len > sizeof(cmd->msg)) {
+                               err = -EINVAL;
+                               break;
+                       }
+                       err = fe->ops.diseqc_send_master_cmd(fe, cmd);
                        fepriv->state = FESTATE_DISEQC;
                        fepriv->status = 0;
                }