From: Joerg Roedel <jroedel@xxxxxxx>
IOMMU drivers that do not support default domains, but make
use of the the group->domain pointer can get that pointer
overwritten with NULL on device add/remove.
Make sure this can't happen by only overwriting the domain
pointer when it is NULL.
Cc: stable@xxxxxxxxxxxxxxx #v4.4+
Fixes: 1228236de5f9 ('iommu: Move default domain allocation to iommu_group_get_for_dev()')
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
drivers/iommu/iommu.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index bfd4f7c..b9df141 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -848,7 +848,8 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev)
if (!group->default_domain) {
group->default_domain = __iommu_domain_alloc(dev->bus,
IOMMU_DOMAIN_DMA);
- group->domain = group->default_domain;
+ if (!group->domain)
+ group->domain = group->default_domain;
}
ret = iommu_group_add_device(group, dev);
--
1.8.4.5
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html