X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fiommu%2Famd_iommu_v2.c;h=7caf2fa237f22bd7a3b0932c6387ed52e0b26424;hb=91737eb0b562e9f9d302b551d071851e68b3bb50;hp=d21d4edf7236abac49072c086290b76d2ae201b5;hpb=80e0c505b22e64ab1787285b182a1e8395e53991;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c
index d21d4edf7236..7caf2fa237f2 100644
--- a/drivers/iommu/amd_iommu_v2.c
+++ b/drivers/iommu/amd_iommu_v2.c
@@ -494,6 +494,22 @@ static void handle_fault_error(struct fault *fault)
 	}
 }
 
+static bool access_error(struct vm_area_struct *vma, struct fault *fault)
+{
+	unsigned long requested = 0;
+
+	if (fault->flags & PPR_FAULT_EXEC)
+		requested |= VM_EXEC;
+
+	if (fault->flags & PPR_FAULT_READ)
+		requested |= VM_READ;
+
+	if (fault->flags & PPR_FAULT_WRITE)
+		requested |= VM_WRITE;
+
+	return (requested & ~vma->vm_flags) != 0;
+}
+
 static void do_fault(struct work_struct *work)
 {
 	struct fault *fault = container_of(work, struct fault, work);
@@ -516,8 +532,8 @@ static void do_fault(struct work_struct *work)
 		goto out;
 	}
 
-	if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE))) {
-		/* handle_mm_fault would BUG_ON() */
+	/* Check if we have the right permissions on the vma */
+	if (access_error(vma, fault)) {
 		up_read(&mm->mmap_sem);
 		handle_fault_error(fault);
 		goto out;