From: Phil Elwell <phil@raspberrypi.org>
Date: Fri, 13 Mar 2015 12:43:36 +0000 (+0000)
Subject: Protect __release_resource against resources without parents
X-Git-Tag: accepted/tizen/unified/20230118.172025~1536
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=43e8fef083f8754bb00cbd15b573aa194f44d5a6;p=platform%2Fkernel%2Flinux-rpi.git

Protect __release_resource against resources without parents

Without this patch, removing a device tree overlay can crash here.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---

diff --git a/kernel/resource.c b/kernel/resource.c
index ca9f519..dd5ac10 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -213,6 +213,12 @@ static int __release_resource(struct resource *old, bool release_child)
 {
 	struct resource *tmp, **p, *chd;
 
+	if (!old->parent) {
+		WARN(old->sibling, "sibling but no parent");
+		if (old->sibling)
+			return -EINVAL;
+		return 0;
+	}
 	p = &old->parent->child;
 	for (;;) {
 		tmp = *p;