mfd: Correct use after free for t7l66xb

The structure t7l66xb should not be freed before the subsequent references
to its fields in the arguments to clk_put.  Furthermore, this structure is
allocated near the beginning of the function, and a goto to the label
err_noirq appears after a successful allocation, so it would seem that the
kfree should be moved down below this label.

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>

diff --git a/drivers/mfd/t7l66xb.c b/drivers/mfd/t7l66xb.c
index e0bbddd..26d9176 100644 (file)
--- a/drivers/mfd/t7l66xb.c
+++ b/drivers/mfd/t7l66xb.c
@@ -403,12 +403,12 @@ static int t7l66xb_probe(struct platform_device *dev)
 err_ioremap:
        release_resource(&t7l66xb->rscr);
 err_request_scr:
-       kfree(t7l66xb);
        clk_put(t7l66xb->clk48m);
 err_clk48m_get:
        clk_put(t7l66xb->clk32k);
 err_clk32k_get:
 err_noirq:
+       kfree(t7l66xb);
        return ret;
 }