[PATCH 4.4 81/91] video: fbdev: cobalt_lcdfb: Handle return NULL error from devm_ioremap

[Greg Kroah-Hartman]

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

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

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


[ Upstream commit 4dcd19bfabaee8f9f4bcf203afba09b98ccbaf76 ]

Here, If devm_ioremap will fail. It will return NULL.
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>
Acked-by: Yoichi Yuasa <yuasa@xxxxxxxxxxxxxx>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/video/fbdev/cobalt_lcdfb.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/video/fbdev/cobalt_lcdfb.c
+++ b/drivers/video/fbdev/cobalt_lcdfb.c
@@ -350,6 +350,11 @@ static int cobalt_lcdfb_probe(struct pla
 	info->screen_size = resource_size(res);
 	info->screen_base = devm_ioremap(&dev->dev, res->start,
 					 info->screen_size);
+	if (!info->screen_base) {
+		framebuffer_release(info);
+		return -ENOMEM;
+	}
+
 	info->fbops = &cobalt_lcd_fbops;
 	info->fix = cobalt_lcdfb_fix;
 	info->fix.smem_start = res->start;