[PATCH] iommu: amd: NULL value may be dereferenced

[Alexander Sapozhnikov]

Pointer 'dom' which was dereferenced at iommu.c:1993 
is compared to NULL value at iommu.c:1998.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Alexander Sapozhnikov <alsp705@xxxxxxxxx>
---
 drivers/iommu/amd/iommu.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index a0924144bac8..64a88e67be9c 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -1985,6 +1985,9 @@ static void amd_iommu_domain_free(struct iommu_domain *dom)
 {
 	struct protection_domain *domain;
 
+	if (!dom)
+		return;
+
 	domain = to_pdomain(dom);
 
 	if (domain->dev_cnt > 0)
-- 
2.40.1