[PATCH] of: overlay: propagate error unflattening DTBO

[Ahmad Fatoum]

of_unflatten_dtb() may return an error pointer when parsing of the
device tree blob failed. Error pointers were not checked in
of_overlay_apply_dtbo() leading to a panic when they were later
dereferenced in of_copy_node().

Add an early exit to fix this.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 drivers/of/overlay.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
index 34543403e9ba..4345489b3b40 100644
--- a/drivers/of/overlay.c
+++ b/drivers/of/overlay.c
@@ -351,6 +351,9 @@ int of_overlay_apply_dtbo(struct device_node *root, const void *dtbo)
 	int ret;
 
 	overlay = of_unflatten_dtb(dtbo, INT_MAX);
+	if (IS_ERR(overlay))
+		return PTR_ERR(overlay);
+
 	ret = of_overlay_apply_tree(root, overlay);
 	of_delete_node(overlay);
 
-- 
2.47.3