[PATCH 4.9 16/66] ata: sata_mv:- Handle return value of devm_ioremap.

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Arvind Yadav <arvind.yadav...@gmail.com>

commit 064c3db9c564cc5be514ac21fb4aa26cc33db746 upstream.

Here, If devm_ioremap will fail. It will return NULL.
Then hpriv->base = NULL - 0x20000; Kernel can run into
a NULL-pointer dereference. This error check will avoid
NULL pointer dereference.

Signed-off-by: Arvind Yadav <arvind.yadav...@gmail.com>
Signed-off-by: Tejun Heo <t...@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/ata/sata_mv.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -4132,6 +4132,9 @@ static int mv_platform_probe(struct plat
        host->iomap = NULL;
        hpriv->base = devm_ioremap(&pdev->dev, res->start,
                                   resource_size(res));
+       if (!hpriv->base)
+               return -ENOMEM;
+
        hpriv->base -= SATAHC0_REG_BASE;
 
        hpriv->clk = clk_get(&pdev->dev, NULL);