From: Jerry Snitselaar <jsnitsel@xxxxxxxxxx>
commit bf708cfb2f4811d1948a88c41ab96587e84ad344 upstream.
It is possible for archdata.iommu to be set to
DEFER_DEVICE_DOMAIN_INFO or DUMMY_DEVICE_DOMAIN_INFO so check for
those values before calling __dmar_remove_one_dev_info. Without a
check it can result in a null pointer dereference. This has been seen
while booting a kdump kernel on an HP dl380 gen9.
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # 5.3+
Cc: linux-kernel@xxxxxxxxxxxxxxx
Fixes: ae23bfb68f28 ("iommu/vt-d: Detach domain before using a private one")
Signed-off-by: Jerry Snitselaar <jsnitsel@xxxxxxxxxx>
Acked-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/iommu/intel-iommu.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -5132,7 +5132,8 @@ static void dmar_remove_one_dev_info(str
spin_lock_irqsave(&device_domain_lock, flags);
info = dev->archdata.iommu;
- if (info)
+ if (info && info != DEFER_DEVICE_DOMAIN_INFO
+ && info != DUMMY_DEVICE_DOMAIN_INFO)
__dmar_remove_one_dev_info(info);
spin_unlock_irqrestore(&device_domain_lock, flags);
}
