[PATCH 3.2 090/199] ata: sata_mv:- Handle return value of devm_ioremap.

[Ben Hutchings]

3.2.87-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>

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.cs@xxxxxxxxx>
Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/ata/sata_mv.c | 3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -4059,6 +4059,9 @@ 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;
 
 #if defined(CONFIG_HAVE_CLK)