[PATCH 4.9 088/105] video: fbdev: cobalt_lcdfb: Handle return NULL error from devm_ioremap

From: Greg Kroah-Hartman
Date: Fri Aug 04 2017 - 19:24:23 EST


4.9-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
@@ -308,6 +308,11 @@ 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;