drivers/serial/sunsu.c: Correct use after free

The of_iounmap is at the out_unmap label, but at that point up has already
been freed.  The free cannot be moved to the out_unmap label, because that
label is reachable from cases where up should not be freed.  So the call to
of_iounmap is just duplicated, and the goto converted to a return.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,e;
identifier f;
iterator I;
statement S;
@@

*kfree(x);
... when != &x
    when != x = e
    when != I(x,...) S
*x->f
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/serial/sunsu.c b/drivers/serial/sunsu.c
index 170d3d6..cbcfb18 100644 (file)
--- a/drivers/serial/sunsu.c
+++ b/drivers/serial/sunsu.c
@@ -1453,8 +1453,10 @@ static int __devinit su_probe(struct of_device *op, const struct of_device_id *m
        if (up->su_type == SU_PORT_KBD || up->su_type == SU_PORT_MS) {
                err = sunsu_kbd_ms_init(up);
                if (err) {
+                       of_iounmap(&op->resource[0],
+                                  up->port.membase, up->reg_size);
                        kfree(up);
-                       goto out_unmap;
+                       return err;
                }
                dev_set_drvdata(&op->dev, up);