[PATCH 5.10 177/452] drm/msm/hdmi: check return value after calling platform_get_resource_byname()

[Greg Kroah-Hartman]

From: Yang Yingliang <yangyingliang@xxxxxxxxxx>

[ Upstream commit a36e506711548df923ceb7ec9f6001375be799a5 ]

It will cause null-ptr-deref if platform_get_resource_byname() returns NULL,
we need check the return value.

Fixes: c6a57a50ad56 ("drm/msm/hdmi: add hdmi hdcp support (V3)")
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Patchwork: https://patchwork.freedesktop.org/patch/482992/
Link: https://lore.kernel.org/r/20220422032227.2991553-1-yangyingliang@xxxxxxxxxx
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/msm/hdmi/hdmi.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/msm/hdmi/hdmi.c b/drivers/gpu/drm/msm/hdmi/hdmi.c
index 94f948ef279d..2758b51aa4e0 100644
--- a/drivers/gpu/drm/msm/hdmi/hdmi.c
+++ b/drivers/gpu/drm/msm/hdmi/hdmi.c
@@ -142,6 +142,10 @@ static struct hdmi *msm_hdmi_init(struct platform_device *pdev)
 	/* HDCP needs physical address of hdmi register */
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
 		config->mmio_name);
+	if (!res) {
+		ret = -EINVAL;
+		goto fail;
+	}
 	hdmi->mmio_phy_addr = res->start;
 
 	hdmi->qfprom_mmio = msm_ioremap(pdev,
-- 
2.35.1