From: Yang Yingliang <yangyingliang@huawei.com>
Date: Mon, 25 Apr 2022 19:45:25 +0800
Subject: iommu/arm-smmu-v3: check return value after calling
 platform_get_resource()
Git-commit: b131fa8c1d2afd05d0b7598621114674289c2fbb
Patch-mainline: v5.19-rc1
References: bsc#1205701

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

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20220425114525.2651143-1-yangyingliang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Acked-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 627a3ed5ee8f..88817a3376ef 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -3770,6 +3770,8 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 
 	/* Base address */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -EINVAL;
 	if (resource_size(res) < arm_smmu_resource_size(smmu)) {
 		dev_err(dev, "MMIO region too small (%pr)\n", res);
 		return -EINVAL;