[PATCH 5.4 305/411] rtc: mt6397: check return value after calling platform_get_resource()

From: Greg Kroah-Hartman
Date: Mon Jun 13 2022 - 07:37:36 EST


From: Yang Yingliang <yangyingliang@xxxxxxxxxx>

[ Upstream commit d3b43eb505bffb8e4cdf6800c15660c001553fe6 ]

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

Fixes: fc2979118f3f ("rtc: mediatek: Add MT6397 RTC driver")
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220505125043.1594771-1-yangyingliang@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/rtc/rtc-mt6397.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/rtc/rtc-mt6397.c b/drivers/rtc/rtc-mt6397.c
index b216bdcba0da..dd3901b0a4ed 100644
--- a/drivers/rtc/rtc-mt6397.c
+++ b/drivers/rtc/rtc-mt6397.c
@@ -331,6 +331,8 @@ static int mtk_rtc_probe(struct platform_device *pdev)
return -ENOMEM;

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
rtc->addr_base = res->start;

rtc->irq = platform_get_irq(pdev, 0);
--
2.35.1