Merge tag 'iommu-fixes-v5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu fixes from Joerg Roedel:

 - A couple more fixes for the Intel VT-d driver for bugs introduced
   during the recent conversion of this driver to use IOMMU core default
   domains.

 - Fix for common dma-iommu code to make sure MSI mappings happen in the
   correct domain for a device.

 - Fix a corner case in the handling of sg-lists in dma-iommu code that
   might cause dma_length to be truncated.

 - Mark a switch as fall-through in arm-smmu code.

* tag 'iommu-fixes-v5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Fix possible use-after-free of private domain
  iommu/vt-d: Detach domain before using a private one
  iommu/dma: Handle SG length overflow better
  iommu/vt-d: Correctly check format of page table in debugfs
  iommu/vt-d: Detach domain when move device out of group
  iommu/arm-smmu: Mark expected switch fall-through
  iommu/dma: Handle MSI mappings separately

1 files changed, 9 insertions, 2 deletions

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index bdaed2da8a55..12d094d08c0a 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -3449,6 +3449,7 @@ static bool iommu_need_mapping(struct device *dev)
 				dmar_domain = to_dmar_domain(domain);
 				dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
 			}
+			dmar_remove_one_dev_info(dev);
 			get_private_domain_for_dev(dev);
 		}
 
@@ -4790,7 +4791,8 @@ static void __dmar_remove_one_dev_info(struct device_domain_info *info)
 
 	/* free the private domain */
 	if (domain->flags & DOMAIN_FLAG_LOSE_CHILDREN &&
-	    !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY))
+	    !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) &&
+	    list_empty(&domain->devices))
 		domain_exit(info->domain);
 
 	free_devinfo_mem(info);
@@ -4803,7 +4805,8 @@ static void dmar_remove_one_dev_info(struct device *dev)
 
 	spin_lock_irqsave(&device_domain_lock, flags);
 	info = dev->archdata.iommu;
-	__dmar_remove_one_dev_info(info);
+	if (info)
+		__dmar_remove_one_dev_info(info);
 	spin_unlock_irqrestore(&device_domain_lock, flags);
 }
 
@@ -5281,6 +5284,7 @@ static int intel_iommu_add_device(struct device *dev)
 		if (device_def_domain_type(dev) == IOMMU_DOMAIN_IDENTITY) {
 			ret = iommu_request_dm_for_dev(dev);
 			if (ret) {
+				dmar_remove_one_dev_info(dev);
 				dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
 				domain_add_dev_info(si_domain, dev);
 				dev_info(dev,
@@ -5291,6 +5295,7 @@ static int intel_iommu_add_device(struct device *dev)
 		if (device_def_domain_type(dev) == IOMMU_DOMAIN_DMA) {
 			ret = iommu_request_dma_domain_for_dev(dev);
 			if (ret) {
+				dmar_remove_one_dev_info(dev);
 				dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
 				if (!get_private_domain_for_dev(dev)) {
 					dev_warn(dev,
@@ -5316,6 +5321,8 @@ static void intel_iommu_remove_device(struct device *dev)
 	if (!iommu)
 		return;
 
+	dmar_remove_one_dev_info(dev);
+
 	iommu_group_remove_device(dev);
 
 	iommu_device_unlink(&iommu->iommu, dev);