Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
IronPort-SDR: b4ouB7Ow4Gn5yfmqbt4f1g+53HOgJwg5KD4Hr/J0YjX5azJFPytyBRSeLePu+wg99iKxW2/w6b
 jHd1pnXfCYi/WDSl1FWYStzX8E56ux3GP8m6ac3eJ6fAmRk1hvOIUxZ9uejNN+3glcKl38UwvB
 kedngjXsYoN/yVWXLZXHAoBQ/a+qSPnn1uq5zBDWfDFbuRfrvsO3KqEsFEZKMfFW9R8464cwqX
 0QMx+vowv96oRB2G2N0QxL2oBfSllsPb5GcJYN9MF+oNFq0Fc5H3l93sk5nCF8H3oc7ygb3FG3
 fU8=
IronPort-PHdr: =?us-ascii?q?9a23=3AMofmWhZUDb9se7lPNsHc2JL/LSx+4OfEezUN45?=
 =?us-ascii?q?9isYplN5qZoMW+bnLW6fgltlLVR4KTs6sC17OM9fm+AidQuN6oizMrSNR0TR?=
 =?us-ascii?q?gLiMEbzUQLIfWuLgnFFsPsdDEwB89YVVVorDmROElRH9viNRWJ+iXhpTEdFQ?=
 =?us-ascii?q?/iOgVrO+/7BpDdj9it1+C15pbffxhEiCCybL9vMhm6txjdu8gYjIdtKas91w?=
 =?us-ascii?q?bCr2dVdehR2W5mP0+YkQzm5se38p5j8iBQtOwk+sVdT6j0fLk2QKJBAjg+PG?=
 =?us-ascii?q?87+MPktR/YTQuS/XQcSXkZkgBJAwfe8h73WIr6vzbguep83CmaOtD2TawxVD?=
 =?us-ascii?q?+/4apnVAPkhSEaPDMi7mrZltJ/g75aoBK5phxw3YjUYJ2ONPFjeq/RZM4WSX?=
 =?us-ascii?q?ZdUspUUSFBB4K8b5AUD+oAO+ZYoJT2qUUXoxCjCwmsBf3gyjtViXTr2aE33f?=
 =?us-ascii?q?gtHQTA0Qc9HdwBrW7Uoc31OqkMTO67wqrGwzLYYv9KxTvw8pTEfwo9rf2QW7?=
 =?us-ascii?q?97bMrfyVMoFwPAllifq43lPjKV1uQQtGiQ8u1tVOKuim4nsQ5xoySjytsih4?=
 =?us-ascii?q?TSm4Ia1krE+T9nz4koON21UUh2asOnHptIryyWKZd6T8c4T2xruCs20KMKtY?=
 =?us-ascii?q?OncCQQ1ZgqwxzSZ+Saf4WJ5h/vTvidLDl4iX5/Zr6yhgy+/Eqvx+D6S8K6yk?=
 =?us-ascii?q?xFrjBfndnJrn0N0hvT5dWZRfZl5Ueh3CqP1xjU6uFZPUA4jarbJIAlwr43jp?=
 =?us-ascii?q?cTtF7MHi7ymEnvlK+WeFgo9vGm6+j6ZrjrpIWQN4BzigH5PaQuntKwDf4kPQ?=
 =?us-ascii?q?gJWmiX4eW81Lv98k3lWLhGkOE6n63DvJ3ZJckXvLC1DxJJ3oo59hqyCzWr3M?=
 =?us-ascii?q?wdnXYdLVJFfByHj5LuO1HLOP35Dfa+g1S2nzdq2/zKIrPsD47QLnffirftZ6?=
 =?us-ascii?q?hy5FNByAYr19BQ+4pUCq0dIPL0QkLxsN3YDhkkMw272urnC8ty1pkYWW2RBq?=
 =?us-ascii?q?+UK73SsVCW6eI1OeWMZ5EauCz7K/c74/7il3g5mUUSffrh84EQbSWJH+ZmPk?=
 =?us-ascii?q?LRNWv+gt4AST9Rlhc1VqrnhEDUAm0bXGq7Q69pvmJzM4mhF4qWA9/1jQ=3D?=
 =?us-ascii?q?=3D?=
From:   Yizhuo <yzhai003@ucr.edu>
Cc:     csong@cs.ucr.edu, zhiyunq@cs.ucr.edu, Yizhuo <yzhai003@ucr.edu>,
        Alex Deucher <alexander.deucher@amd.com>,
        =?UTF-8?q?Christian=20K=C3=B6nig?= <christian.koenig@amd.com>,
        David Airlie <airlied@linux.ie>, amd-gfx@lists.freedesktop.org,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: [PATCH] drm/amd/powerplay: Variable ps could be NULL when it get dereferenced
Date:   Thu, 29 Aug 2019 21:35:04 -0700
Message-Id: <20190830043504.23760-1-yzhai003@ucr.edu>
To:     unlisted-recipients:; (no To-header on input)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Inside function cz_get_performance_level(), pointer ps could be NULL via
cast_const_PhwCzPowerState(). However, this pointer is dereferenced
without any check, which is potentially unsafe.

Signed-off-by: Yizhuo <yzhai003@ucr.edu>
---
 drivers/gpu/drm/amd/powerplay/hwmgr/cz_hwmgr.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/amd/powerplay/hwmgr/cz_hwmgr.c b/drivers/gpu/drm/amd/powerplay/hwmgr/cz_hwmgr.c
index bc839ff0bdd0..d2628e7b612d 100644
--- a/drivers/gpu/drm/amd/powerplay/hwmgr/cz_hwmgr.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/cz_hwmgr.c
@@ -1799,6 +1799,9 @@ static int cz_get_performance_level(struct pp_hwmgr *hwmgr, const struct pp_hw_p
 	data = (struct cz_hwmgr *)(hwmgr->backend);
 	ps = cast_const_PhwCzPowerState(state);
 
+	if (!ps)
+		return -EINVAL;
+
 	level_index = index > ps->level - 1 ? ps->level - 1 : index;
 	level->coreClock = ps->levels[level_index].engineClock;
 
-- 
2.17.1