4.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joerg Roedel <jroedel@xxxxxxx> commit eebb8034a5be8c2177cbf07ca2ecd2ff8a058958 upstream. 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. Fixes: 1228236de5f9 ('iommu: Move default domain allocation to iommu_group_get_for_dev()') Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iommu/iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -848,7 +848,8 @@ struct iommu_group *iommu_group_get_for_ 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); -- 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