From: Stefan Wahren <stefan.wahren@i2se.com>
Date: Sun, 23 Jan 2022 20:02:21 +0000 (+0100)
Subject: staging: vchiq_arm: Avoid NULL ptr deref in vchiq_dump_platform_instances
X-Git-Tag: v5.16.20~170
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4627250cabaa80278d3ab01ad107893cea83799f;p=thirdparty%2Fkernel%2Fstable.git

staging: vchiq_arm: Avoid NULL ptr deref in vchiq_dump_platform_instances

[ Upstream commit aa899e686d442c63d50f4d369cc02dbbf0941cb0 ]

vchiq_get_state() can return a NULL pointer. So handle this cases and
avoid a NULL pointer derefence in vchiq_dump_platform_instances.

Reviewed-by: Nicolas Saenz Julienne <nsaenz@kernel.org>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/1642968143-19281-17-git-send-email-stefan.wahren@i2se.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
index b9505bb51f45c..de25140159e39 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
@@ -1209,6 +1209,9 @@ int vchiq_dump_platform_instances(void *dump_context)
 	int len;
 	int i;
 
+	if (!state)
+		return -ENOTCONN;
+
 	/*
 	 * There is no list of instances, so instead scan all services,
 	 * marking those that have been dumped.