From: Jan Kiszka <jan.kiszka@siemens.com>
Date: Tue, 2 Nov 2010 07:05:51 +0000 (+0100)
Subject: intel-iommu: Fix use after release during device attach
X-Git-Tag: v2.6.35.13~7
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=62e2d392a18f2a3149e31fecbe18a32a06587174;p=thirdparty%2Fkernel%2Fstable.git

intel-iommu: Fix use after release during device attach

upstream commit 7a6610139a

Obtain the new pgd pointer before releasing the page containing this
value.

Cc: stable@kernel.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
---

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 83ac0a08f701f..46fcc591d5ed9 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -3638,9 +3638,9 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
 
 		pte = dmar_domain->pgd;
 		if (dma_pte_present(pte)) {
-			free_pgtable_page(dmar_domain->pgd);
 			dmar_domain->pgd = (struct dma_pte *)
 				phys_to_virt(dma_pte_addr(pte));
+			free_pgtable_page(pte);
 		}
 		dmar_domain->agaw--;
 	}