drivers/dma: Correct use after free
Julia Lawall [Tue, 22 Dec 2009 20:30:59 +0000 (21:30 +0100)]
Move the kfree after the iounmap that refers to the same structure.

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: Dan Williams <dan.j.williams@intel.com>

drivers/dma/coh901318.c

index 4a99cd9..b5f2ee0 100644 (file)
@@ -1294,8 +1294,8 @@ static int __exit coh901318_remove(struct platform_device *pdev)
        dma_async_device_unregister(&base->dma_slave);
        coh901318_pool_destroy(&base->pool);
        free_irq(platform_get_irq(pdev, 0), base);
-       kfree(base);
        iounmap(base->virtbase);
+       kfree(base);
        release_mem_region(pdev->resource->start,
                           resource_size(pdev->resource));
        return 0;