This is a note to let you know that I've just added the patch titled
vfio/type1: Use follow_pte()
to the 5.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
vfio-type1-use-follow_pte.patch
and it can be found in the queue-5.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 07956b6269d3ed05d854233d5bb776dca91751dd Mon Sep 17 00:00:00 2001
From: Alex Williamson <alex.williamson@xxxxxxxxxx>
Date: Tue, 16 Feb 2021 15:49:34 -0700
Subject: vfio/type1: Use follow_pte()
From: Alex Williamson <alex.williamson@xxxxxxxxxx>
commit 07956b6269d3ed05d854233d5bb776dca91751dd upstream.
follow_pfn() doesn't make sure that we're using the correct page
protections, get the pte with follow_pte() so that we can test
protections and get the pfn from the pte.
Fixes: 5cbf3264bc71 ("vfio/type1: Fix VA->PA translation for PFNMAP VMAs in vaddr_get_pfn()")
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
Reviewed-by: Peter Xu <peterx@xxxxxxxxxx>
Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/vfio/vfio_iommu_type1.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -24,6 +24,7 @@
#include <linux/compat.h>
#include <linux/device.h>
#include <linux/fs.h>
+#include <linux/highmem.h>
#include <linux/iommu.h>
#include <linux/module.h>
#include <linux/mm.h>
@@ -431,9 +432,11 @@ static int follow_fault_pfn(struct vm_ar
unsigned long vaddr, unsigned long *pfn,
bool write_fault)
{
+ pte_t *ptep;
+ spinlock_t *ptl;
int ret;
- ret = follow_pfn(vma, vaddr, pfn);
+ ret = follow_pte(vma->vm_mm, vaddr, &ptep, &ptl);
if (ret) {
bool unlocked = false;
@@ -447,9 +450,17 @@ static int follow_fault_pfn(struct vm_ar
if (ret)
return ret;
- ret = follow_pfn(vma, vaddr, pfn);
+ ret = follow_pte(vma->vm_mm, vaddr, &ptep, &ptl);
+ if (ret)
+ return ret;
}
+ if (write_fault && !pte_write(*ptep))
+ ret = -EFAULT;
+ else
+ *pfn = pte_pfn(*ptep);
+
+ pte_unmap_unlock(ptep, ptl);
return ret;
}
Patches currently in stable-queue which might be from alex.williamson@xxxxxxxxxx are
queue-5.11/vfio-type1-use-follow_pte.patch
