[PATCH 5.9 103/152] iommu: Check return of __iommu_attach_device()

[Greg Kroah-Hartman]

From: Shameer Kolothum <shameerali.kolothum.th...@huawei.com>

[ Upstream commit 77c38c8cf52ef715bfc5cab3d14222d4f3e776e2 ]

Currently iommu_create_device_direct_mappings() is called
without checking the return of __iommu_attach_device(). This
may result in failures in iommu driver if dev attach returns
error.

Fixes: ce574c27ae27 ("iommu: Move iommu_group_create_direct_mappings() out of 
iommu_group_add_device()")
Signed-off-by: Shameer Kolothum <shameerali.kolothum.th...@huawei.com>
Link: 
https://lore.kernel.org/r/20201119165846.34180-1-shameerali.kolothum.th...@huawei.com
Signed-off-by: Will Deacon <w...@kernel.org>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 drivers/iommu/iommu.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 609bd25bf154b..6a0a79e3f5641 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -264,16 +264,18 @@ int iommu_probe_device(struct device *dev)
         */
        iommu_alloc_default_domain(group, dev);
 
-       if (group->default_domain)
+       if (group->default_domain) {
                ret = __iommu_attach_device(group->default_domain, dev);
+               if (ret) {
+                       iommu_group_put(group);
+                       goto err_release;
+               }
+       }
 
        iommu_create_device_direct_mappings(group, dev);
 
        iommu_group_put(group);
 
-       if (ret)
-               goto err_release;
-
        if (ops->probe_finalize)
                ops->probe_finalize(dev);
 
-- 
2.27.0